Quick to-dos for writing better subject lines

From wine labels and book covers to blind dates, the truth is, it’s human nature to judge something at first sight. It may not always be accurate, or fair, but it happens. Many people often choose a wine based on how much we like the label. Of course, books are judged by their cover, hence the reason for the commonly applied adage telling us not to. And you know what they say about making a good first impression on a date. The same initial judgement is true for emails. The subject line—the first impression for emails—greatly affects whether that email will be opened and read. It’s the wine label, book cover, and first impression for an email that offers the opportunity to get your recipient to pay attention and act.

When it comes to writing email subject lines, there are best practices that, when followed, can significantly increase the likelihood of enticing your audience to open and engage with your emails. Below is a mix of best practices and what I’ve adopted in practice over the years to help improve your open rates.

1. Short and sweet

The shorter you can keep your subject line the better off you’ll be. To help ensure your subject line doesn’t get cut off, it’s best to keep your character count less than 40 characters, including spaces. But since it’s always good to have goals, shoot for 30 if you can. Plus, the lower the character count the better when you consider a couple things about mobile:

  • Subject lines on mobile show even fewer character.
  • Roughly two-thirds of emails are opened on a mobile device these days.

So, get to the point when it comes to subject lines. Save the creative spin for the email itself. But hey, if you can turn a phrase that says what you need it to in a few words, you most likely have yourself a winning subject line.

2. Sender names that make sense

It’s been asked if using your company’s name or your own name is best. In the simplest of terms, there are two types of email, marketing emails and personal correspondence between two people or a small group. We’ll ignore the latter for now because it’s common sense. So, when deciding the sender’s name for emails, it’s best to use your company name for a few reasons:

  • It immediately allows the recipient to know who the email is from, and doesn’t misguide someone by them thinking it’s spam.
  • Having the sender name as your company name will save you from having to establish it in the subject line, therefore saving character count for other important info.
  • It also helps the recipient if they need to search for an email. Inputting the company name in search criteria makes it much easier to sift through a lineup of search results.

Some companies also use categorical descriptors as part of their sender name. For example, Southwest Airlines sends emails with different sender names, such as “Southwest Airlines,” “Southwest Click ‘N Save,” and “Southwest Airlines Rapid.” Each incorporates the company name while giving you an idea of what to expect and the purpose of the email prior to even reading the subject line.

3. Special Characters

Turns out special characters aren’t that special after all. They haven’t shown to increase open rates, but are known to trigger spam filters more frequently than not using them. Rule of thumb is to stay away. That said, we know rules are tempting to break, so depending on the special characters you want to use, you might be alright. Although, in general, I’m not a fan of ellipses, and often see them misused, they are much less likely to trigger a spam filter than exclamation points—another overly misused character.

4. Sense of urgency

Taking the time to incorporate some urgency into your subject line could yield dividends for your ROI. Whether you attempt to create urgency for the opening of the email itself or the action you want the recipient to take after reading the email, in general, providing some sort of urgency in your subject line can increase open rates by approximately 22%. Specifically, using “tomorrow” in your subject line can increase open rates by 10% more than those without. And using “alert” increases it 61.8% more.

5. Ask questions

A personal favorite subject line style of mine is posing a question in a subject line. Not only do they tend to perform better, but it’s human nature—whether consciously or not—to assess the question and likely answer it. At that point, you already have some amount of engagement. If the question is on point and relates to the recipient, you’re likely to get an opened email. To create a question that answers the call for being good subject line material, consider your audience’s likes, dislikes, and needs related to your email topic.

6. Don’t overdo caps or exclamation points


7. A/B test

The process for writing the perfect subject line isn’t an exact science. Often the only way to determine what works best is A/B testing. This will help you get a better idea of what works and what doesn’t. To do so, decide what you want to test, but pick only one factor to test at a time. Maybe it’s offer based vs not; two separate offers; question vs statement; or using emojis vs not. Whatever it is, two sets of emails will be sent to different sets of recipients. When it comes to the winning scenario, you can set up your email platform to automatically choose the winning campaign and send away. Or, you can choose it manually based on the data. Either way, if you’re like me, you’ll enjoy reviewing the data to see if your instinct was right.

8. To emoji or not to emoji

To stand out from the multitude of emails wanting someone’s attention, adding a colorful emoji to your subject line can help. However, there are some guidelines you should follow:

  • Know your audience
  • Make it relevant to the subject line
  • Less is more. Keep it to a minimum.
  • Use them to enhance the words you write, not replace them.

Also, if you’d like to see how the assortment of emojis appear for different vendors, Unicode provides a list of emoji characters.

9. Lead with an offer

Chances are, you’re reaching out to people because you have something you or your client feels they’ll want. Whether it’s a free offer or discount, a notification, or any number of other reasons, your best bet for getting them to open your email is to let them know upfront what you have for them. I often lead the reader along by writing my subject lines, headlines, and body copy in a manner where each builds upon the next. At each stage, give them a little more useful information until, ideally, they reach the call to action.

10. Make it personal

Catering to the customer has never been so easy. One way to do so is personalizing the subject line of your email with the recipient’s first name. Using emerge tags to do so can greatly increase open rates.

Ok, what now?

Now that you know some of the more critical guidelines to creating successful subject lines, it’s time to go forth and write. Test the 10 tips above and see how they work for you. Combined with your own writing style, you’ll have results to rave about in no time. And, of course, when in doubt, A/B test your way to finding the answer that works best for you and your client.