Cold Outeach
8 min read

How to Write Subject Lines for Cold emails (Contains 136 Ready to use Subject lines)

Contains 136 Ready to use Subject lines. Your ultimate guide to crafting attention-grabbing, click-worthy, and downright irresistible email subject lines.
Written by
Vikas Jha
Published on
June 25, 2023

Crafting Your Subject Line

Contains 136 Ready to use Subject lines.

"Dive into the fascinating world of email subject lines with this guide' - your ultimate guide to crafting attention-grabbing, click-worthy, and downright irresistible email subject lines. The insightful case studies, unique perspectives, and practical tips will leave you awe-struck and inspire you to test the boundaries of your creativity while adhering to the proven strategies that ensure your emails stand out in the crowded inbox.

Whether crafting an event invitation, a newsletter, a sales promotion, or a cold outreach email, 'Line It Up!' provides a treasure trove of tested and proven strategies to improve your open rates, boost your engagement, and drive conversions. 

What's more? 

You'll also learn how to avoid the common pitfalls and 'sins' in email marketing to consistently deliver value to your audience while maintaining your brand's credibility.

It's time to arm yourself with the power of effective subject lines, get ready to 'Line It Up!', and watch your email campaign metrics soar!"

The Psychology of Subject Lines

Understanding their minds is the best way to capture your audience's attention. This means understanding the psychological principles that affect how people perceive and respond to communication. 

Here are some significant psychological principles to consider when crafting your subject lines.

  1. Curiosity: As humans, we have a natural desire to seek out new knowledge and experiences. Curiosity is a powerful psychological trigger that can compel people to open your emails. Subject lines that tease interesting content or offer unique insights can ignite a recipient's curiosity.
  2. Scarcity: People tend to place a higher value on items, opportunities, or information they perceive as scarce. This principle can be used in your subject lines to create a sense of urgency, encouraging recipients to open the email before it's too late. For instance, "Limited Spots Available for Our Webinar, {{First_Name}}" gives a sense of exclusivity.
  3. Social Proof: Social proof is a psychological phenomenon where people conform to the actions of others, assuming they reflect the correct behaviour. In your subject lines, you can use social proof by including statistics or mentioning satisfied customers.
  4. Reciprocity: People generally feel obliged to give back when they receive something. Offering something of value in your subject line, like a helpful guide or a free trial, can induce a feeling of reciprocity, which might compel your recipients to respond.

The Art of Brevity: Keeping It Short and Sweet

Subject lines aren't the place for detailed explanations or lengthy pitches. They need to be short, snappy, and to the point. Here's how to master the art of brevity.

  1. Concise Messaging: Aim to communicate your message in as few words as possible. Ideally, your subject line should be under 50 characters to ensure it's fully visible in most email clients.
  2. Clear Value Proposition: Make it clear what your recipient stands to gain by opening your email. This should be evident from your subject line.
  3. Avoid Fillers: Words like 'just', 'really', 'very', etc. don't add much value and just take up precious space. They can also weaken your message.

Emphasising Value: What's In It for Them?

The recipient of your email will likely ask one question: "What's in it for me?" Your email will likely be opened if your subject line can answer that question convincingly.

  1. Benefits Over Features: Instead of focusing on the features of your product or service highlight the benefits. How will it help the recipient? Will it save them time? Make them more money? Solve a problem they have?
  2. Provide Solutions: If you understand your audience's challenges and pain points, you can craft subject lines that offer solutions. "Eliminate Cold Calling Stress, {{First_Name}}" could appeal to salespeople who struggle with cold calling.
  3. Free Stuff: Everyone loves getting something for nothing. Say so in your subject line if you're offering something for free—a guide, a webinar, or a trial.

Crafting compelling subject lines requires a delicate balance of art and science. Understanding the psychology of your audience, mastering the art of brevity, and emphasising value are vital components of this process. As you gain more experience and collect more data on your audience's preferences, your subject lines will become even more effective.

Personalisation: Beyond First Names

Personalisation is a potent tool in email marketing, including in subject lines. However, it goes beyond simply dropping a prospect's first name into the subject line. Overusing first names in subject lines can feel impersonal and robotic if it's not done right. 

Here's how to take your personalisation game to the next level:

  1. Understand Your Recipient: The more you know about the recipient, the more personal and relevant your subject line can be. Information about their job role, industry, challenges they face, and their goals can help you craft a subject line that truly resonates with them.
  2. Segmentation: Not all your recipients are the same, so why should all your subject lines be? Segment your email list based on different parameters such as industry, job role, or past behaviour, and tailor your subject lines accordingly. This can drastically increase relevance and, therefore, open rates.
  3. Personalisation Tokens: Personalization tokens can insert unique information into each subject line. This could be the recipient's name, company name, location, or any other information you have about them. However, make sure that your use of personalisation tokens makes sense in the context of your subject line. A subject line like "How Our Product Can Help {{Company_Name}} Improve Sales" feels much more personal and relevant than just "Improve Sales, {{First_Name}}."
  4. Behaviour-Based Personalization: This is where personalisation can get powerful. Using your data on how your recipients have interacted with your previous emails or your website, you can create subject lines based on their behaviour. For example, if a recipient downloaded a guide on social media marketing from your website, you could send them an email with a subject line like "More Social Media Tips, {{First_Name}}?"

Remember, the key to effective personalisation is relevance. Your subject line should make your recipient feel like the email was specifically meant for them, not just anyone. As Dale Carnegie once said, "A person's name is to him or her the sweetest and most important sound in any language." But it's not just about the name; it's about showing that you understand and care about their needs and interests.

Contextualization: Nailing the Relevance

The journey from your email landing in a prospect's inbox to them actually opening it, largely relies on context. Contextualisation adds a dimension of relevance to your subject line, resonating with your recipient's current situation or environment. Let's explore how you can use contextualisation to breathe life into your subject lines:

  1. Event-based Contextualization: Timing your email with a recent or upcoming industry event can yield high open rates. For instance, if a prospect's company recently secured a funding round, a subject line like "Congratulations on the funding, {{First_Name}}! Let's talk growth" can demonstrate your awareness and invite a conversation.
  2. Location-specific Contextualization: Knowing where your prospect is based can be valuable. For example, if you're planning to visit their city, a subject line like "Visiting {{City}} next week, fancy a coffee, {{First_Name}}?" can break the ice and open up opportunities for face-to-face interaction.
  3. Action-triggered Contextualization: An action taken by the recipient can be a potent context for your subject line. For instance, if a prospect downloaded a white paper from your website, a subject line such as "Thoughts on our white paper, {{First_Name}}? Let's discuss!" can continue the conversation.
  4. Interest-driven Contextualization: If you know your prospect's professional interests or challenges, use it in your subject line. For instance, if a prospect has shown interest in AI technology, you could use a subject line like "Exploring AI possibilities at {{Company}}, {{First_Name}}?"
  5. Company Milestone-based Contextualization: Company achievements like anniversaries or award recognitions can be used to add a personal touch. A subject line like "Kudos on the Best Startup award, {{First_Name}}! How can we help scale your success?" would resonate and show alignment with their joy.

Contextualization is about striking the chord of relevance with your prospect. The more your subject line echoes their current situation, the higher your chances of getting that email opened. Remember, when you hit the proper context, your email ceases to be a pitch and transforms into a meaningful conversation.

Emotional Triggers and Subject Lines

Emotions can be powerful drivers of action. They can sway our decisions, stir our passions, and compel us to act in ways that logic and reason might not. In email marketing and sales, understanding and employing emotional triggers in your subject lines can be a game-changer. Let's delve into the captivating realm of emotional triggers and see how they can spice up your subject lines.

Understanding Emotional Triggers

In the simplest of terms, an emotional trigger evokes a strong emotional response. These triggers can be highly personal, tapping into an individual's experiences, values, aspirations, or fears. However, common emotional triggers also affect large swaths of people.

Understanding these universal triggers can help you craft subject lines that resonate on a deeper emotional level with your recipients. Here are some examples of universal emotional triggers:

  • Curiosity: People are innately curious; a subject line that piques this curiosity can be incredibly effective.
  • Fear: Fear is a potent motivator, and fear of missing out (FOMO) can push people to take action.
  • Desire: Tapping into people's desires (for success, knowledge, happiness, etc.) can drive engagement.
  • Surprise: Unexpected or novel information can catch people's attention and encourage them to learn more.

Now that we understand emotional triggers let's explore how to use them to enhance our subject lines.

Eliciting Curiosity with Your Subject Line

Curiosity is a powerful force. It's what drives us to explore the unknown, to ask questions, and to seek answers. You can leverage this innate human trait to create subject lines that practically beg to be opened.

Here's an example:

  • "Uncovered: The secret behind {{Company}}'s skyrocketing growth"

In this subject line, we've teased some valuable information (the secret behind a company's success) without giving away the specifics. This piques the recipient's curiosity and makes them want to open the email to learn more.

But be careful not to overdo it. A subject line that's too vague can frustrate the recipient and make them less likely to open your email. Always strive for a balance between intriguing your recipients and providing them with enough information to know what the email is about.

Using Fear of Missing Out (FOMO) in Your Subject Line

The fear of missing out, or FOMO, is another powerful emotional trigger. It plays on our natural fear of being left behind or missing out on something valuable or exciting.

Use time-sensitive language or suggest exclusivity to evoke FOMO in your subject lines. Here are a couple of examples:

  • "Final chance: Join the elite 5% of sales pros excelling at cold emails."
  • "Exclusive: Your personalised sales masterclass is expiring soon!"

Both subject lines create a sense of urgency and exclusivity, making the recipient more likely to open the email to avoid missing out on the opportunity. But again, caution is needed when using FOMO. If every email you send suggests the recipient is about to miss out on a once-in-a-lifetime opportunity, they'll quickly ignore your messages.

Remember, using emotional triggers in your subject lines isn't about manipulation. It's about understanding what drives people and speaking to those drivers authentically and respectfully. Always keep your recipient's needs and preferences in mind, and strive to provide value with every message you send.

The Art of Personalization and Localization

In an era where our inboxes are inundated with impersonal, often irrelevant emails, personalization and localization serve as a beacon, guiding us towards more meaningful and engaging content. For sales development representatives, account executives, and marketing professionals, mastering these techniques can be the key to unlocking higher open rates, better engagement, and more conversions.

The Intricacies of Personalization

Personalization is an art. Done well, it can create a unique connection between your company and each recipient of your emails. However, it's about much more than just addressing recipients by their first names. While this can help to create an immediate sense of familiarity, true personalization extends much further.

Consider this personalized subject line:

"Maximize Your Sales, {{First_Name}}: Our Platform Can Help."

Here, we're not just using the recipient's first name. We also recognise that they likely aim to increase sales and position our product as a potential solution. This isn't generic - it's personalized to a specific role and potential need.

Now, let's take it a step further. Say you're reaching out to a prospect who you know has just been promoted to head of sales at their company:

"Congrats on Your Promotion, {{First_Name}} - Ready to Boost Your Sales?"

This subject line addresses the recipient by name and acknowledges a recent event in their professional life. This level of personalisation can catch their attention and make them feel more valued and understood.

Embracing Localization

Localization goes hand in hand with personalization. While personalization speaks to who the recipient is, localization speaks to where they are - physically and contextually. This could mean referencing a local event, speaking the recipient's language, or acknowledging a trend or issue specific to their location.

An example could be:

"{{First_Name}}, Win the SF Market with Our Real Estate Insights!"

In this case, we're not just addressing the recipient by name. We're also referencing their location (San Francisco) and their industry (real estate), and positioning our product as a tool to help them succeed in their local market.

This approach can make the email feel more relevant and appealing, increasing the chances of it being opened.

The Pitfall of Over-Personalization

While personalization can be a powerful tool, it can also backfire if not handled with care. Over-personalization - using personal data inappropriately or excessively - can make recipients feel uncomfortable or invaded.

Using the previous examples, a subject line like this could potentially fall into the over-personalization trap:

"{{First_Name}}, We Saw You Visited Our Pricing Page - Ready to Buy?"

This subject line might be too intrusive, making the recipient feel monitored rather than understood. Therefore, it's vital to balance personalisation with respect for privacy and personal boundaries.

Contextualisation: The Next Level of Personalization

Contextualization involves aligning your subject line with the recipient's specific context or situation. This could be related to their job role, their industry, a challenge they're facing, or a goal they're trying to achieve.

For instance, if you're reaching out to a prospect in the healthcare industry who's recently shown interest in your product, a contextualized subject line might look like this:

"Streamline Patient Care, {{First_Name}} - Let's Talk Solutions"

Here, we've used the recipient's first name and tailored the subject line to their specific industry and a likely goal or challenge within that industry. This increases the relevance and appeal of the email, making it more likely to be opened.

The combination of Personalization, Localization, and Contextualization

Combining all three elements - personalization, localization, and contextualization - can yield a potent subject line that resonates with the recipient on multiple levels. 

Let's explore an example:

"{{First_Name}}, Boost Austin's E-commerce with Our Proven Strategies."

In this subject line, we've personalised it using the recipient's first name, localized it by referencing their location (Austin), and contextualized it by aligning our offer with their role or industry (e-commerce). Such a combination increases the odds of our email being opened, read, and acted upon.

The Risk of Mis-Personalization and Mis-Localization

While personalization and localization can be highly effective, they also carry risks if implemented poorly or based on incorrect data. Mis-personalization - using the wrong name, title, or other personal details - can damage the recipient's perception of your brand and reduce the likelihood of your email being opened.

Similarly, mis-localization - referencing an incorrect location or making an inaccurate local reference - can also detract from your email's effectiveness. Thus, it's crucial to ensure the accuracy of your data before using it in your subject lines.

Test, Analyze, and Adjust

As with many aspects of sales and marketing, it's essential to continually test, analyze, and adjust your approach to personalization and localization. Monitor your open rates, click-through rates, and conversion rates to assess the effectiveness of different types of subject lines.

Do personalized subject lines yield higher open rates? 

Do localized subject lines lead to more clicks or conversions? 

By analyzing your data, you can gain valuable insights to help refine your approach and enhance the effectiveness of your subject lines.

As we move forward, we must continually strive to improve our understanding of our recipients and tailor our subject lines accordingly. Personalization and localisation will continue to play a significant role in this process, but they must always be applied thoughtfully and ethically.

The goal isn't merely to increase open rates or clicks. It's to build genuine connections and relationships with our recipients, add value to their lives and careers, and ultimately turn them into loyal customers and advocates for our brand. Let's embark on this journey together and unlock the full potential of our subject lines.

Subject Lines for Different Purposes - Delving Deeper

Email subject lines aren't one-size-fits-all. They must be carefully crafted to fit the purpose of each unique email. Let's explore this further, taking a deeper dive into how subject lines can be honed for event invitations, newsletters, sales promotions, and cold emails. Along the way, we'll dissect each example, unpacking its components to illustrate why it works.

Event Invitation Subject Lines

In events, the invitation's subject line serves as your first impression, your grand entrance. Here, you need to convey excitement, exclusivity, and importance.

Consider the example, "You're Invited: TechCon 2023 on June 25 – Don't Miss Out!" This subject line starts with a personal touch, "You're Invited," implying that the recipient is valued. It follows with specific details, the event's name and date, giving it substance. Lastly, it instils a sense of urgency with "Don't Miss Out!" This trifecta of personalization, detail, and urgency is a potent recipe for event subject lines.

Newsletter Subject Lines

Newsletters aim to provide value through information, updates, or insights. The subject line's job here is to act as a preview, giving recipients a taste of what they'll get if they open the email.

In the example, "Your Monthly AI Digest: Unpacking Deep Learning This Week," the term "Your Monthly AI Digest" sets the context – the reader can expect a regular dose of AI-related content. The phrase "Unpacking Deep Learning This Week" tells the reader precisely what they will learn. This subject line effectively balances anticipation with clarity, sparking curiosity without veiling the content in mystery.

Sales and Promotional Email Subject Lines

Sales and promotional emails require a compelling mix of urgency and value. They must convey that something good awaits the reader, but it won't wait forever.

Take the subject line, "Flash Sale: Get 50% Off Our Premium Plan – Only 24 Hours Left!"

It creates a strong sense of urgency with "Flash Sale" and "Only 24 Hours Left!".

But it doesn't stop at urgency; it also communicates a substantial value proposition, "Get 50% Off Our Premium Plan". This subject line hits that sweet spot where urgency meets value, encouraging the recipient to act fast and open the email.

Cold Email Subject Lines

Cold emails are arguably the trickiest of the bunch. Here you are, reaching out to someone who might not have heard of you or your organization. The subject line must capture interest, distinguish itself in a crowded inbox, and extend an intriguing invitation for further engagement.

Consider this example: "On Your Marks, Get SEO, Grow! 5% in 60 days." To capture attention, this subject line uses a playful adaptation of a familiar phrase ("On your marks, get set, go!"). It's unexpected and quirky, which can be enough to make someone pause in their inbox scrolling.

The subject line then transitions into the value proposition: SEO growth. Specifically, it promises a 5% growth in 60 days. This gives the recipient a clear idea of what to expect from the email. It's not just about SEO; it's about growth and measurable results, which will likely resonate with anyone striving to improve their website's performance.

But notice how this subject line is not overly personal. It doesn't include the recipient's first name or their company's name. This is a strategic choice. Over-personalisation can sometimes feel forced or even invasive in a cold email, where the sender and recipient have no established relationship.

Instead, this subject line opts for contextualization. It implicitly acknowledges the recipient's need (improving SEO performance) and positions its offer as a solution. This combination of capturing attention, offering clear value, and sensitively contextualizing its message makes this subject line a strong contender in the challenging arena of cold emails.

Cold email subject lines are your first step in building a relationship with your recipient. You want to intrigue and invite, not push or presume. A great subject line respects the recipient's needs and curiosity, offering value without imposing commitment. And most importantly, it paves the way for a conversation, which is, after all, the ultimate goal of any cold email.

The Role of Humor, Wit, and Creativity

The power of humor, wit, and creativity can be leveraged to elevate your email subject lines from standard to standout. When wielded with precision, these elements can intrigue and compel the recipient to open your email. In this chapter, we'll take a closer look at how to effectively infuse these elements into your subject lines, drawing from examples that have turned heads and won clicks.

The Art of Being Funny in Subject Lines

Humor is a potent tool for generating interest and making a memorable impression. But here's the catch: humor in subject lines isn't about randomly inserting a joke or a pun. It must be relevant, relatable, and respectful.

Take, for instance, the subject line: "Feeling 'sheet' out of luck? Try our new Bedding Line!" The brand cleverly substitutes 'sheet' for slang, creating a playful connection to its product.

This subject line works because it checks all the right boxes. It's relevant using a pun that ties directly to the product being promoted. It's relatable, invoking a feeling that resonates with many of us. And it's respectful, avoiding humor that could potentially offend.

Now, consider a cold email example: "Exhausted? We're your 'espresso' button for better sales." This subject line is especially effective because it uses humor to address a common sentiment among its intended audience (sales professionals often working long hours) and ties it to the product's value proposition - a boost in sales akin to the energy jolt from an espresso.

Injecting Creativity into Your Subject Lines

Creativity in your subject lines is about differentiating yourself from the typical inbox clutter. It involves using unexpected language, fresh ideas, or surprising connections to captivate your recipient.

Let's revisit our previous example: "Coffee meets Bagel; You meet Incredible Success." This B2B subject line cleverly mirrors the phrasing of a popular dating app, creating an unexpected yet familiar start that hooks the reader.

This subject line stands out because it leverages familiarity, surprises with a twist, and segues into a compelling proposition. But creativity should not be an end in itself; it must always serve the message and resonate with the audience.

Look at a creative cold email subject line: "Your Success Story is Waiting to be Written." This line takes a different approach by painting a visual image and inspiring curiosity about what success could look like for the recipient. It's a strong hook encouraging them to open the email and learn more.

Remember, while humor, wit, and creativity can make your subject lines pop, they must be used strategically and purposefully. They should amplify your message, not muddy it. In the sections, we will delve deeper into these tools and how they can work synergistically with other techniques to create powerful subject lines. So, stay with us on this journey towards more compelling and creative email marketing.

Testing and Optimizing Your Subject Lines

If you consider email marketing an art form, A/B testing is the meticulous brush stroke that refines your masterpiece. It's an iterative process that strives to understand your audience better and optimise your subject lines to evoke maximum engagement. 

This chapter explains why testing is critical, how to learn from your data, and the importance of continuous improvement.

The Importance of A/B Testing

A/B testing, also known as split testing, compares two versions of a subject line to see which one performs better. Let's take a cold email example: "Increase your sales by 50% with our software" versus "Our software: Your secret weapon for 50% more sales." They both communicate the same promise but with different framing.

The first subject line is straightforward and benefit-focused. It puts the results front and centre. However, the second line gives a spin of mystery and exclusivity by referring to the software as a 'secret weapon.'

Which one would work better? That's where A/B testing comes in. It offers empirical data to back your decisions, ensuring they aren't based solely on hunches.

Learning from Your Data

Once your A/B test is complete, delving into the data and gleaning insights is crucial. Pay close attention to metrics like open rates, click-through rates, and conversion rates.

If "Our software: Your secret weapon for 50% more sales" garners a higher open rate, your audience responds better to subject lines that evoke curiosity and exclusivity.

However, if the first subject line leads to more conversions, it implies that while the second line may pique interest, the straightforward promise of the first line persuades recipients to take action.

The key here is not just to collect data but interpret it wisely. It's about connecting the dots to understand your audience's preferences and adapting your approach.

Continuous Improvement: The Path to Mastering Subject Lines

In email marketing, change is the only constant. User behaviour shifts, trends evolve, and what works today may not work tomorrow. Mastering subject lines is a journey of continuous learning and refinement.

Consider your successful A/B tests not as the end, but as stepping stones towards better understanding your audience. Don't rest on your laurels; use these insights as a foundation to build upon. Continually challenge your assumptions, test new ideas, and strive to push the envelope.

Remember, the power of a compelling subject line goes beyond just one email. It represents your brand's voice, signifies your understanding of your audience, and is often the first step towards building a lasting relationship with your customer.

A/B testing and optimization isn't about chasing a 'perfect' subject line— it's about mastering the ability to consistently create subject lines that resonate with your audience and incite action. It's a path of perpetual growth, pushing your marketing efforts towards higher levels of success.

Tools and Techniques for A/B Testing

While the concept of A/B testing is straightforward, effectively implementing it can be a complex process, particularly when dealing with many variables. Fortunately, numerous tools are available to streamline this process. For instance, email marketing platforms often have built-in features for A/B testing that automate the process, providing clear and actionable data.

Consider a hypothetical situation where you have two subject lines for a sales outreach email:

  1. "Cut your operational costs by 20% in 3 months"
  2. "Want to reduce operational costs? We have a solution."

The A/B testing tool would send these subject lines to a small fraction of your recipient list. It would automatically select the better-performing subject line for the rest of the list based on initial responses.

It's not just about choosing between two options, either. You can also conduct multivariate testing, where multiple elements are tested simultaneously to see how they perform in different combinations. This can provide a more nuanced understanding of your audience's preferences.

Moreover, A/B testing isn’t exclusive to subject lines. You can (and should) use it to test other elements of your email, such as the call to action, body copy, imagery, and layout. The idea is to comprehensively understand what resonates with your audience and what doesn’t.

Interpreting A/B Test Results

Analyzing the results of your A/B tests can sometimes feel like reading tea leaves. However, with a systematic approach, you can extract valuable insights from the data.

Let's assume that the first subject line in our previous example had a higher open rate, but the second one led to more conversions. This suggests that while a direct benefit (like cutting costs by 20%) may grab attention, posing a question and hinting at a solution might engage recipients deeper, compelling them to take action.

However, ensuring that your results are statistically significant and not just random variations is crucial. You don’t want to base your decisions on fluke results. Tools can help here, with built-in features to determine the significance of your test results.

The Iterative Nature of A/B Testing

A/B testing is not a one-and-done activity. It's an iterative process that needs to be repeated regularly to adapt to changing trends and audience behaviour.

Your audience’s reaction to subject lines can change over time due to numerous factors - changing market conditions, shifting consumer sentiment, or even the evolving relationship between your brand and your customers. Therefore, a subject line that worked well a year ago might not yield the same results today.

Hence, the mantra is to keep testing, keep learning, and keep optimizing. With each iteration, you get closer to mastering the art of writing subject lines.

And remember, the journey to mastering subject lines isn’t a sprint; it’s a marathon. It requires patience, persistence, and a willingness to learn and adapt. But the rewards, in terms of higher engagement, conversions, and sales, are well worth the effort.

Best Practices and Sins to Avoid in Crafting Subject Lines

Crafting an effective subject line is an art that requires a balance of creativity, empathy, and understanding of various elements. This chapter will cover essential best practices and common pitfalls to avoid while creating your subject lines.

The Device Dilemma: Crafting Subject Lines for Different Devices

In our fast-paced digital world, your audience will likely read your emails on various devices: desktops, laptops, tablets, and, increasingly, smartphones. Each device has a different display limit for email subject lines, meaning that a lengthy subject line that appears in full on a desktop email client might get cut off on a mobile device.

A good rule of thumb is to aim for a subject line length of 40-45 characters to ensure it's visible on most devices. Also, remember to place your most crucial information or offer at the beginning of the subject line, where it's least likely to get cut off.

Consider the subject line: "Ready to boost your sales productivity by 30%? Discover our new tool." On a mobile device, this might appear as "Ready to boost your sales producti..." Losing the latter part of your message could diminish the impact. A better approach might be: "Boost sales productivity by 30% with our new tool." This version puts the value proposition first, reducing the impact of any truncation.

Before finalising your subject line, it's best practice to send a test email to see how it appears on different devices. This will allow you to make any necessary adjustments before hitting send.

Navigating the Spam Filter: Words to Avoid in Subject Lines

Email providers use sophisticated algorithms to filter out spam messages, and these algorithms pay close attention to the words used in your subject lines. Certain words and phrases, especially those related to sales and promotions, can trigger spam filters, causing your email to end up in the spam folder.

Some common spam trigger words include "guarantee", "free", "risk-free", "save", "discount", and "cash". It's advisable to avoid these unless they're necessary for your message. Instead, focus on crafting a subject line that communicates value and relevance to the recipient without sounding overly promotional.

Combatting Inbox Clutter: Standing Out in a Crowded Inbox

In a crowded inbox, your email has to compete with dozens, if not hundreds, of other messages for the recipient's attention. Therefore, your subject line needs to be not just catchy but also unique and differentiated.

Using personalization is one way to stand out. But as we discussed earlier, it has to be meaningful personalization. A subject line like "{{First_Name}}, want to boost your team's productivity?" is more likely to get noticed than a generic "Boost your team's productivity."

Another tactic is to incorporate timely or topical elements. A subject line like "5 productivity tools for remote work" would resonate with people working from home due to the COVID-19 pandemic.

Understanding and Respecting Cultural Differences

If your audience spans different countries and cultures, it's crucial to consider cultural nuances. What works well in one culture might not resonate, or worse, might offend in another.

For instance, humor can be highly culture-specific. A funny subject line that works well in the US might not be understood or might appear inappropriate in Japan. Always be mindful of these cultural differences and consider employing localisation strategies for different regions.

Avoiding False Promises and Clickbait: The Importance of Authenticity

In a bid to increase open rates, making bold promises in your subject lines can be tempting. However, if the content of your email doesn't deliver on these promises, it can lead to disappointment, erode trust, and increase unsubscribe rates. Authenticity is key. Ensure that your subject line accurately reflects the content of your email.

Similarly, avoid using clickbait strategies, such as overly sensational or mysterious language. Clickbait may lead to a short-term increase in open rates, but it can harm your brand's credibility in the long run. Remember, your goal is to build a long-term relationship with your readers, not just to get one-off opens.

Over-Personalization: Walking the Fine Line

Personalization is a powerful tool for making your emails more relevant and engaging. However, over-personalization can make your emails feel intrusive or creepy, turning off your recipients.

It's essential to balance personalisation and respect for your recipient's privacy. Use personalisation to show your recipient that you understand their needs and interests, but avoid using personal details that the recipient might feel uncomfortable seeing in an email.

For instance, a subject line like "John, save on your next trip to Paris!" is personalised and relevant if John has recently been browsing Paris flights on your website. On the other hand, a subject line like "John, ready for your upcoming surgery?" might feel intrusive and inappropriate, even if John has recently purchased medical supplies from your website.

Beware of Overuse of Capitals and Exclamation Marks

Using ALL CAPS or multiple exclamation marks can make your subject line appear as shouting and potentially trigger spam filters. This approach can also make your email look unprofessional, and it's likely to turn off recipients.

Instead, use capitalisation and punctuation sparingly and appropriately to emphasize key points. For example, "Get your free guide today!" is a more professional and appealing subject line than "GET YOUR FREE GUIDE TODAY!!!"

Understanding and implementing these best practices and avoiding common pitfalls can create compelling subject lines that resonate with your audience, leading to higher open rates and engagement. The key is always to keep your recipient at the centre of your strategy, crafting subject lines that offer them clear value and relevance.

Appendix: Subject Line Templates for Various Industries

This section presents multiple subject line templates, each tailored for specific industries. These templates can serve as the inspiration you need to draft your compelling subject lines. To ensure understanding, I'll break down each subject line, explaining its underlying effectiveness and the psychological cues it's tapping into.

SEO Services

"Skyrocket {{CompanyName}}'s Organic Traffic by 102%"

This subject line appeals to the recipient's desire to dramatically improve their website's organic traffic. The personalization and use of a specific number (102%) enhance credibility and promises a substantial benefit.

"Unlock 5% Growth in 60 Days with a proven SEO Process"

Here, the keywords 'Unlock' and 'proven' create a sense of exclusivity, implying that the recipient will gain access to an effective and tested SEO process. The promise of a tangible 5% growth in a specific timeframe (60 days) provides clarity and sets expectations.

"On Your Marks, Get SEO, Grow! 5% in 60 days"

This subject line is engaging and playful, starting with a call to action inspired by the common phrase used to initiate races. The mention of a specific percentage (5%) and timeframe (60 days) communicates transparency and commitment.

"60 Days + Proven process = 5% Growth Surge"

This one uses the equation format to deliver a simple yet effective message, ensuring easy understanding. It implies that applying the 'proven process' over '60 days' will result in a '5% Growth Surge'.

"Trim Cost, Hit Goals: SEO Success Guaranteed"

The subject line promises dual benefits - cutting costs and achieving goals. The use of 'Guaranteed' seals the deal by providing an extra layer of assurance and trust.

Marketing Agencies/SaaS

"From Clicks to Footsteps: The O2O Masterstroke"

This subject line introduces the idea of bridging the gap between online actions and offline outcomes. The term 'Masterstroke' indicates an expert strategy or a superior solution.

"Influencers: Your Love-Potion for Sales!"

This one creatively plays on the love potion metaphor, suggesting the powerful attraction of influencers in driving sales. It's a fun way of stating the power of influencer marketing.

"Pinch-Hitter for Your Paid Marketing"

A baseball metaphor suggesting the service can serve as a vital substitute or saviour to the recipient's existing paid marketing efforts. 'Pinch-Hitter' conveys the readiness to step in and perform, making it highly engaging.

"CAC on Diet, Revenue on Steroids!"

This subject line is concise, clever, and playful. It promises two substantial benefits - reducing Customer Acquisition Cost (CAC) and increasing revenue, goals that every business aims to achieve.

Love Potion #9 - 🔥Up Your Conversion Rates

The subject line "Love Potion #9 - 🔥Up Your Conversion Rates" effectively combines intrigue and direct benefits. "Love Potion #9" is a familiar song reference, suggesting an enticing, magical solution for customer attraction. The fire emoji intensifies the promise to increase conversion rates, directly appealing to a common business goal. This blend of familiarity, curiosity, and clear benefits makes the subject line compelling and encourages email opens.

"💘Profit at First Play: Casting Conversion Spell"

This subject line plays with the concept of magic and love to emphasize the idea that using the promoted service will create a conversion 'spell' leading to instant profits.

"Dull to Dazzle - Boost conversion by X%"

Here, the transition from 'Dull to Dazzle' promises a significant change, reinforced by the promise of boosting conversions by a certain percentage. Including the potential boost can prompt curiosity about how such an increase can be achieved.

"Puzzle-Me-Not, {{First_Name}}: Up CTR by 30%"

This subject line uses playful language to depict the service as a solution that is easy and not puzzling. The promise to 'Up CTR by 30%' gives a precise performance metric, which increases the appeal of the offer.

"Romeo & Revenue: 200% Sales Jump Overnight!"

By linking the romantic tale of Romeo to revenue, this subject line catches the eye. The promise of a '200% Sales Jump Overnight!' suggests a dramatic increase in sales, which can arouse interest.

"{{First_Name}}, Magically reduce CPL by 35%"

Personalized with the recipient's name and proposing a magical reduction in Cost Per Lead (CPL), this subject line sparks curiosity. Quantifying the reduction in CPL can prompt recipients to open the email to find out more.

"Find Hidden Gold in Your Data, {{First_Name}}! 💰"

This subject line suggests that valuable insights (the 'Hidden Gold') can be unearthed from the recipient's data. The gold and money bag emojis underline the idea of value and profit.

"Unlock Your Data's Power, {{First_Name}}! 🔓"

Here, the subject line metaphorically represents the data as something powerful that has been locked away. The proposed service is the key to unlocking this power. The lock emoji visually reinforces this idea.

"Unmask Unseen Customer Insight 🎭"

This subject line plays on the metaphor of masks and drama, implying that the service will help reveal valuable, currently unseen insights about customers.

"Boost Your ROAS by 34% 🚀"

The direct promise to 'Boost Your ROAS by 34%' is clear and compelling, offering a specific and measurable benefit. The rocket emoji visually conveys the idea of a boost.

"Your Marketing Cheat Codes, {{First_Name}}! 🎮"

By likening the proposed service to 'cheat codes' in a game, this subject line suggests that using it will provide a shortcut or easy route to success. The video game controller emoji emphasizes the gaming metaphor.

Each of these subject lines creatively presents a compelling proposition while using playful and engaging language. They pique the reader's interest and curiosity, encouraging them to open the email to learn more about the offer.


"Step up, {{First_Name}} - Your Team Needs a Hero!"

This subject line plays on the superhero theme, suggesting that the recipient can be the 'hero' their team needs. It creates a narrative that the product/service being offered can help them 'step up'.

"Bird? Plane? No, {{First_Name}}, It's You!"

Here, the subject line is playing off the classic Superman line. This tactic aims to make the recipient feel special and consequential, like they can 'soar' above their challenges with the product/service being offered.

"Rocket Your Results, {{First_Name}}!"

Using the verb 'Rocket' implies a fast and substantial improvement in results. Coupled with personalisation, it directly speaks to the recipient's desires.

"ESG Compliance in 7 days"

This subject line is short, sweet, and extremely direct. It promises a fast solution to a complex problem—achieving ESG (Environmental, Social, and Governance) compliance. The specificity of '7 days' adds a sense of urgency and makes the proposition more attractive.

"Simplify {{companyName}}'s Digital Asset Management!"

This subject line addresses a common need for many businesses—simplified digital asset management. By incorporating the company's name, the subject line is personalized and thus more compelling.

"No More ESG Reporting in the Dark, {{First_Name}}"

This line combines a strong negative command, 'No More', with a problem - 'ESG Reporting in the Dark'. By using the recipient's name, it promises a personalized solution to a frustrating issue.

"{{First_Name}}, Ace Your ESG Reporting Game"

Here, 'Ace' is used as a motivational verb to encourage the reader to excel in their 'ESG Reporting Game', suggesting that the company's offering will help them improve.

"Goodbye One-Size-Fits-All ESG"

This subject line communicates that the company understands the frustrations of generic solutions and suggests that they have a more tailored, effective approach to ESG.

"2.6x Revenue Jump? It's Possible, {{First_Name}}"

This subject line stirs the reader's curiosity with a provocative question. The personalized reassurance that follows ('It's Possible, {{First_Name}}') suggests that the solution provided can make this substantial increase in revenue a reality.

HR Services

{{First_Name}}, Assemble Dream Team in 45 Days"

This subject line uses personalization and a clear timeframe to present a solution to the common challenge of hiring, making it appealing to HR managers. It implies a fast, effective hiring process that can yield high-quality results.

"Close 27 Vacancies in 45 Days, {{First_Name}}"

This line highlights a specific achievement, closing 27 vacancies in 45 days, which is a strong incentive for recipients facing similar hiring challenges. It promises a solution to expedite their hiring process.

"100% Perfect Hires, Every Time, {{First_Name}}"

The promise of "perfect hires" every time offers an attractive proposition to hiring managers. It taps into the desire for reliability and quality in the recruitment process.

"From 15 to 9 Vacancies in 30 Days, {{First_Name}}"

This subject line uses specific figures to show impressive results achieved within a short timeframe. It serves as an attractive promise for recipients struggling with numerous vacancies.

"Boost Hiring with Proven 10-Step Search"

The concept of a "proven 10-step search" offers a concrete and structured solution to boost hiring, appealing to recipients who seek effectiveness and organization in their hiring processes.

"🚫 Ditch Hiring Disasters, {{First_Name}}"

This line cleverly uses an emoji for visual impact and humor, while the message strongly resonates with anyone who has faced difficulties in hiring. It promises a solution to avoid such pitfalls.

"Get Your Hiring Superpowers, {{First_Name}}"

This subject line employs the concept of "superpowers", making the promise of enhanced capabilities in hiring, which is enticing for recipients seeking to improve their HR performance.

"Assemble Your Dream Team, {{First_Name}} 🎯"

Using the phrase "dream team" and the target emoji, this subject line presents an enticing goal for HR managers - forming the ideal team. It implies that the content will offer a method to achieve this goal.

"🧩 Your Dream Team Awaits, {{First_Name}}"

The puzzle emoji suggests that the email will provide the missing pieces to complete the "dream team". It's a compelling message promising a solution to the recipient's hiring needs.

IT Services

"Mix'n Match Cloud: Your Recipe for 35% Savings"

This subject line implies customization and flexibility with the phrase 'Mix'n Match'. The enticing promise of a 35% savings could spark curiosity, prompting the recipient to open the email to find out more.

"Wave Goodbye to Workflow Nightmares"

This subject line appeals to anyone who has experienced difficulties with managing workflows. The phrase 'Wave Goodbye' creates a strong visual and emotional resonance, implying an easy solution to their 'nightmares'.

"End the Workflow Drama Today, {{First_Name}}"

Similar to the above, this subject line addresses the common pain point of workflow issues. The call to 'End the Workflow Drama Today' creates urgency and offers a clear solution.

"{{First_Name}}, Grab the Controls of Your CI/CD! 🕹️"

The subject line is empowering, implying that the recipient can take charge of their Continuous Integration/Continuous Deployment (CI/CD) with the product or service offered. The joystick emoji adds a playful touch.

"Mute the Noise of False Alarms! 📢"

This subject line cleverly uses the 'Mute the Noise' metaphor to indicate the reduction or elimination of unnecessary alerts or 'false alarms' in an IT environment.

Remember, these subject lines are templates. Feel free to adapt and modify them to suit your industry, audience, and offer. Above all, the most effective subject lines are those that genuinely reflect your brand voice and resonate with your audience's needs and interests. 

More Examples

Project Management Software:

  • "Boost Productivity by 50% with Smart PM."
  • "Meet Deadlines 100%, Every Time, {{First_Name}}"
  • "From Chaos to Order: Manage 2x More Projects"
  • "Get More Done: Optimize Your Project Flow 📈"
  • "Project Management Made Easy for {{First_Name}} 🔧"

Customer Relationship Management (CRM) Software:

  • "Boost Sales by 35% with Deeper Insights"
  • "{{First_Name}}, Unlock the Power of Your CRM Data 🔐"
  • "Get 3X Closer to Your Customers, Boost Sales"
  • "Skyrocket Your Retention Rate by 60% 🚀"
  • "Discover a New 5-Star Way to Engage Your Customers ⭐"

Marketing Automation Software:

  • "Automate Marketing, Maximize ROI by 70%"
  • "Transform Your Marketing Strategy, {{First_Name}} 🔄"
  • "Elevate Marketing: Automate and Grow 2X 🌱"
  • "Power Up Your Campaigns with Automation ⚡"
  • "Your Marketing Supercharger Awaits, Boost ROI by 45%"

Human Resource Management (HRM) Software:

  • "Simplify HR Tasks, Focus on People 💼"
  • "{{First_Name}}, Make HR Management 3X Easier"
  • "Unleash Your HR Potential with Smart Tech 💪"
  • "Streamline HR Tasks, Boost Engagement by 40%"
  • "From Hires to Retire: Your HR Solution in 30 Days ⏳"

E-commerce Software:

  • "Grow Your E-commerce Business 2.5X Faster 🚀"
  • "Your Online Success Starts Here, Gain 50% More Sales 🎯"
  • "Boost E-commerce Sales with Optimized Tech 💻"
  • "Increase Conversions by 30%, {{First_Name}}"
  • "E-commerce Simplified, Save 15 Hours a Week ⏰"

Enterprise Resource Planning (ERP) Software:

  • "Unify Your Business Processes - Reach New Heights 🏔️"
  • "Your One-Stop Solution for Budgeting, Risk Management and More"
  • "Outsmart the Competition - Get an ERP Edge!"
  • "Efficiently Manage Your Business with the Right ERP Solution 🌐"
  • "Unlock Your Business's Full Potential with ERP"

Accounting Software:

  • "Revolutionize Your Finance Management Today 💰"
  • "{{First_Name}}, Get a Clear Picture of Your Finances 📊"
  • "Accounting Simplified, Profits Magnified!"
  • "Your Path to Smoother Financial Operations Starts Here 💼"
  • "Easily Handle Your Finances: Stay in the Green Zone 💹"

Content Management System (CMS) and E-commerce Platforms:

  • "E-commerce Success Is Just a Click Away 🖱️"
  • "Take Your Online Business to the Next Level with Powerful CMS"
  • "Elevate Your Brand with the Perfect E-commerce Platform 🛍️"
  • "{{First_Name}}, Create, Edit, Publish Content Seamlessly"
  • "E-commerce and CMS: Your Dual Power for Online Success 🚀"

Communication Platforms:

  • "Streamline Business Communications like Never Before 📞"
  • "{{First_Name}}, Instant Messaging & File Sharing at Your Fingertips"
  • "Boost Your Team's Collaboration with Real-Time Communication 🗣️"
  • "Your Solution for Seamless, Global Team Communication"
  • "Connect, Communicate, Collaborate: Revolutionize Workplace Interaction 🌍"

HR/HRM Solutions:

  • "Upgrade Your HR Process: Efficient Recruiting, Scheduling, and More"
  • "{{First_Name}}, Maximize Your Employee Performance 📈"
  • "Effective HR Solutions: Build the Best Team 💪"
  • "Human Resource Management: Streamlined for Your Success 🏅"
  • "Unlock the Potential of Your Human Resources with HRM"

Payment Gateways and Billing Solutions:

  • "Simplify Payments and Increase Your Sales 💳"
  • "Fast, Secure, Easy: The Perfect Payment Solution for Your Business"
  • "Get Your Business Paid Quicker with Advanced Billing Solutions"
  • "{{First_Name}}, Say Goodbye to Billing Hassles 💰"
  • "Secure Payment Gateways: The Key to Trust and Growth 🗝️"

Digital Marketing Agencies:

  • "🚀 Turbocharge Your Online Presence Now"
  • "Increase Lead Conversion with Expert Help"
  • "SEO, PPC, SMM – Unleash Your Growth Trio"
  • "Conquer the Digital Arena, Boost ROI"
  • "🎯 Hit the Bullseye with Precision Marketing"

Public Relations (PR) Agencies:

  • "📢 Amplify Your Brand's Story, Propel Forward"
  • "Get Ready to Dominate the Headlines"
  • "The PR Edge: Cutting Through the Noise 📰"
  • "Control the Conversation, Shape Perception"
  • "Reputation Management for Long-Term Success"

Creative Design Agencies:

  • "Bold Designs to Skyrocket Your Brand 🚀"
  • "🎨 Visual Storytelling to Captivate Audiences"
  • "Stand Out in a Crowd with Creative Flair"
  • "Designs That Connect, Convince, and Convert"
  • "Make a Bold, Unforgettable Statement"

Advertising Agencies:

  • "Ads That Don't Just Speak, They Sell! 🔔"
  • "🎯 Nail Your Audience with Spot-on Ads"
  • "Transform Clicks to Customers, Ads to Sales"
  • "Make Your Ads Unskippable and Irresistible"
  • "Creative Ads That Build Brands and Loyalty"

Real Estate Agencies:

  • "🏡 Your Dream Home is Just a Click Away"
  • "Property Search Made Easy and Rewarding"
  • "Best Properties, Best Prices, Best Service"
  • "Invest Wisely, Reap the Benefits 🌱"
  • "Discover Your Perfect Property Match Today!"

HR Agencies:

  • "🚀 Hire Smart, Grow Fast, Stay Ahead"
  • "Match with Top Talent for Peak Performance"
  • "Your Search for the Perfect Hire Ends Here"
  • "Optimize Your Hiring Process, Save Time"
  • "Attract, Engage, Retain: The HRM Game Plan"

Travel Agencies:

  • "🌍 Your Passport to Unforgettable Experiences"
  • "Turn Your Dream Vacation into Reality"
  • "Travel Smart, Travel Far, Explore More"
  • "Experience Stress-Free Travel Planning"
  • "Discover Destinations, Create Memories 🌅"

What is Alore?

Email Warmer

Generate real engagement to Warm Up Your Email Address without any human intervention

Drip Campaigner

Send emails that generate new business opprotunities for you

Collaborative Inbox

Improve team performance & customer experience - manage multiple email addresses from one place