Ever feel like your carefully crafted emails are landing with a vast pool of unread messages? You’re not alone. A whopping 82% of consumers never even open those emails, according to a Campaign Monitor survey.

But here’s the good news: email marketing still boasts a phenomenal ROI – a staggering 3800% increase for every $1 invested! That means every additional email opened translates to significant revenue potential for your business.

The key to unlocking this email marketing goldmine lies in a crucial first impression: your subject line. It’s the make-or-break factor that determines whether your message gets seen or silently deleted.

Imagine you’re a sales representative at a bustling tech startup. Your inbox is overflowing with emails, each fighting for your attention. Amidst the clutter, one email catches your eye: “Unlock 3X Growth with Our Latest Feature!” Intrigued, you click to open it. That’s the power of a compelling email subject line. According to Invesp, a whopping 47% of email recipients decide whether to open an email based solely on the subject line.

In this post, we’ll crack the code of crafting compelling subject lines that grab attention, spark curiosity, and ultimately get your emails opened! We’ll explore different high-performing subject line types and provide actionable tips to help you write email headlines that turn those “delete” buttons into “open” clicks. 

What is an Email Subject Line, and Why is it Important?

Think of your subject line as the billboard on the highway of your prospect’s inbox. It’s the first impression you make—the one that entices them to open your email. It’s a brief summary that gives the recipient a glimpse of the content inside. Studies by HubSpot show that personalised subject lines can increase open rates by 7.4%. A well-crafted subject line can improve open rates, increase conversions, and strengthen customer relationships.

How to Write Catchy Email Subject Lines: A Recipe for Success

Creating an effective subject line is an art, but with the right formula, you can turn it into a science. It’s the first point of contact—the virtual handshake—that can either pique curiosity or prompt a swift deletion. It requires understanding your customer’s journey, their perception of your brand, and their general state of mind. Here are some examples:

  • Early in the Customer Journey: “Welcome to Salesflow! Let’s Get Started.”
  • Familiar with Your Brand: “Salesflow Update: New Features You’ll Love”
  • General State of Mind: “Feeling Overwhelmed? Salesflow Can Help”

What Makes a Good Email Subject Line?

A good email subject line is brief, personalised, interesting, valuable, urgent, genuine, and keyword-rich. Here are some tips:

  • Keep it brief: You should aim for under 50 characters to ensure readability on mobile devices. As we know about short attention spans and information overload, brevity is key. Studies have shown that subject lines with 6 to 10 words tend to garner the highest open rates, offering a glimpse without overwhelming the recipient. Example: “Boost Your Sales with Salesflow!”
  • Personalise it: Include the recipient’s name or reference a previous interaction for a touch of warmth. Gone are the days of generic mass emails. Personalization is the name of the game. Studies show that personalising subject lines can increase open rates by 7.4% and boost transaction rates by a whopping 6 times.

Leverage customer data and segmentation to tailor your subject lines to individual preferences and behaviours. Example: “John, Increase Your Sales Today!”

1. Make it interesting

Spark curiosity with a question, a surprising statement, or a hint of intrigue. A dose of creativity in your subject lines will help you stand out in a crowded inbox. Example: “Discover the Secret to Tripling Your Revenue”

2. Offer value to your customer or client

Highlight the benefit your email provides, like solving a pain point or offering a discount. Your subject line should be able to convey a clear, tangible benefit or value proposition to the recipient. Whether it’s an exclusive discount, insider knowledge, or actionable insights, highlight what’s in it for them as a reward for opening the email. Example: “Save Time with Salesflow’s Automated Follow-ups”.

3. Build curiosity with your subject lines

Studies show interactive content can boost conversions by 70%! So ditch the boring, and join us for some engagement magic. 

Intrigued? We’ve Got Something Special Inside! Open-ended subject lines like this one can spark curiosity and get your subscribers to peek inside your email.

4. Create urgency (Sparingly)

Use time-sensitive language strategically to encourage immediate action (but avoid sounding spammy!). It’s like harnessing the power of FOMO (fear of missing out) by infusing your subject line with a sense of urgency. 

And there’ s some real benefit of capitalising on FOMO. A whopping 60% of millennial shoppers admit to impulse purchases fueled by FOMO – the fear of missing out. That limited-time offer? The “almost sold out” warning? They trigger a buying frenzy that can benefit your business…if you know how to harness it. Example: “Limited Time Offer: Get Salesflow Today!”

5. Avoid clickbait at all costs

Don’t mislead with false promises; build trust with honesty. Most emails are your conversation starters, and misleading or deceptive subject lines can damage your brand reputation and erode trust with your audience. This might hamper your repeat business and referrals as well. Example: “Learn How Salesflow Can Improve Your Sales Process”

6. Include keywords for better searchability

Optimise your subject lines for searchability by incorporating relevant keywords and phrases. This not only improves your email’s chances of being found but also ensures alignment with recipient expectations. Example: “Automate Your Sales Process with Salesflow”

Now that we’ve understood the anatomy of a winning subject line, let’s explore some practical tips and examples to help you excel in your email game.

Examples of email subject lines based on customer journey and perception

  • New Customer: Subject: “[Name], Welcome to the [Company Name] family! Here’s a Special Gift for You.”
  • Existing Customer: Subject: “Looking to take your experience to the next level, [Name]? We have exciting news for you!”
  • Prospect with Brand Awareness: Subject: “The Secret Weapon [Industry Leaders] Use to [Benefit].” (Think case studies or industry trends.)
  • Prospect Unfamiliar with Brand: Subject: “Is [Pain Point] Holding You Back, [Name]? We can help.” (Address a common pain point in your industry.)

Tips to Get Started

  • Segment your audience: Tailor your subject lines to different audience segments based on demographics, behavior, and preferences. Creating your buyer personas may help you understand the desires or pain points of your potential leads. A one-size-fits-all approach seldom yields optimal results.
  • A/B Test Different Options: Experiment with various subject lines, emojis, and formatting to see what resonates best with your audience. A/B testing allows you to iterate and optimise for maximum impact. Salesflow, an automation tool, can be hugely beneficial here. These tools allow you to send out different versions of your email with different subject lines to a small segment of your list. You can then see which subject line performs best and use that one for the rest of your campaign.
  • Use Strong Verbs: Words like “boost,” “unlock,” or “maximise” can add a sense of empowerment and action.
  • Maintain Brand Consistency: Ensure your subject line aligns with your overall brand voice and tone. Don’t be afraid to inject some personality if it reflects your company’s culture.
  • Monitor and analyse: Leverage analytics tools to track the performance of your subject lines in real-time. Monitor open rates, click-through rates, and conversion metrics for insights and refine your approach accordingly.

Email Subject Line Best Practices (and Some Worst Ones to Avoid)

While the dos and don’ts of subject line creation may seem straightforward, it’s worth highlighting some common pitfalls to steer clear of:

  • Overly salesy language: While the ultimate goal may be to drive sales, overtly promotional subject lines can come across as spammy and turn off recipients.
  • All caps or excessive punctuation: Avoid resorting to gimmicky tactics like excessive capitalization or exclamation marks, which can be perceived as unprofessional and spam-like.
  • Generic or vague subject lines: Be specific and concise in your subject lines to provide clarity and context. Vague or ambiguous subject lines are likely to be overlooked or dismissed as irrelevant.


  • Personalise: “[Name], a quick question about your [area of interest].”
  • Offer Value: “Free Guide: 5 Ways to Increase Your [Industry Metric] by 20%”
  • Create Curiosity: “Is This the Missing Piece to Your Marketing Puzzle?” (Tease a solution without revealing everything.)


  • All caps and excessive exclamation points! Screaming doesn’t build trust.
  • Deceptive Subject Lines: “You Won’t Believe What Happens Next!” = Instant Trash Folder.


Mastering the art of email subject lines can significantly improve your open rates and, ultimately, your bottom line. Remember, the subject line is your first and best opportunity to make a lasting impression. With these tips and best practices, you’re well on your way to crafting subject lines that your recipients can’t resist opening. So, are you ready to unlock the door to improved open rates?

Also read: Understanding Multichannel Outreach to Maximise Sales

Salesflow: Your Partner in Multichannel Outreach

At Salesflow, we understand the importance of a compelling email subject line. Our platform supports multichannel outreach, helping you connect with your customers where they are most comfortable, be it via email or LinkedIn. Sign up today!