9 Ways To Write Great E-mail Subject Lines

Tired of having your e-mails ignored? Here's how to craft a subject line that grabs and keeps your reader's attention.
July 25, 2011

E-mail marketing invokes the golden rule. Do onto your recipients as you would like to receive in your own inbox. You'll find when you ask, “What entices me to open an e-mail?” you’ll find a relevant, compelling subject line at the top of the list.

Yes, subject lines are only 50 short characters. Since those 50 characters can have the biggest impact on the success or failure of your e-mail marketing campaign, it’s worth some effort.

Following, you’ll find nine ways to craft a great subject line.

1. Spend time writing your subject line

I know I’ve been guilty of throwing a subject line in my e-mail service provider’s (ESP) subject line field at the last minute rather than thinking it through. When you actually schedule time to write a compelling subject line, you’ll find a much better result.

2. A/B testing, repeatedly

If your e-mail service provider has the service, try A/B testing to determine which different subject lines work best for your audience. Test every time to find out what kinds of subject lines elicit the greatest response.

About two days before your big e-mail send, take a section of your list and test three or four options for your newsletter or promotional e-mail. I know it sounds like a lot of work, but the math works in your favor.

Consider if each time you test, your best subject line does 9 percent better than your worst subject line. Count up all the times of the year you send a promotional e-mail, then do the math on your revenues with that conservative 9-percent estimate. Increasing your conversion rates (or even open rates) by 9 percent with each e-mail drop can have a huge impact on your long-term ROI.

A/B testing will continue to surprise you. You’ll often find your favorites doing terribly, and the ones you scoffed at quadrupling the open rate. Failure isn’t failure here; it’s just learning. And it can pay off.

Once the winning subject line is chosen, use it for the major send a few hours later.

3. Personalize the subject line 

Subject lines containing the first name of the subscriber always perform better than e-mails without. You can also include other subscriber details such as special offers, purchase history or products of interest. Include other names that recipients would recognize, like the name of your company or an editor’s personal name. Personalized subject lines can help increase open rates up to 64 percent; don’t miss out on an easy addition.

4. Urgency elicits action

Setting a deadline in your subject line can help increase open rates. Short-term promotional offer? Set it up in a series of planned e-mail drops. On Tuesday, tell your recipients they only have four days left. On Thursday follow up with, “Only 24 hours left.” You’ll find that action increases as the deadline approaches.

5. Avoid the spam filter

Avoid the use of terms like FREE!!!, Save $, Lowest Prices, URGENT!, Double Your Sales, !!!, ***, $$$ or all the spammy words you get in the subject line of e-mails that land in your inbox or spam folder. Not only are they red flags to spam filters, they’ll tip your recipients off that there’s nothing of value for them in your e-mail.

6. Don your press hat

Want to write better subject lines? Pick up a newspaper. Newspaper headlines do a great job of highlighting the most important part of a story in a limited number of characters. Newspaper headline writers have years of experience of summarizing their articles (your newsletter content) in a compelling manner.

7. Question your subject line

Ask yourself the following questions about your e-mail before hitting send.

  • What benefit does this subject line infer?  Does the e-mail follow through on that promise?
  • Will the e-mail save the reader money? How is that reflected in the subject line?
  • Will the e-mail improve readers' lives? How is that reflected in the subject line?

8. Put as much relevant information into your subject line as possible

Sending an offer e-mail? Including both the offer details and the product name can help your open rates. If your recipients can trust that the subject lines accurately reflect your content, they’ll continue to open at higher rates than if they feel tricked. That said, you still want to keep an eye on your character limit.

9. Be concise

Leave out unnecessary words. Evaluate greetings to make sure they are needed. By leaving out articles, adjectives and adverbs, you clearly tell the recipient what action to take. Raising curiosity while promising a benefit is a great place to start.

Of course the best thing you can do for your subject line is to always include great, valuable content in your e-mail.

What's the best subject line you've seen lately? Share it in the comments!