How to write effective email subject lines 

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The number one goal of any email marketing campaign is to convert list members into customers. In order for that to happen, they have to first open your email. And, in order for that to happen something has to capture their attention and motivate them to click. That "something" is your email subject line. 

Research says you only have 3 seconds or less to grab a person's attention and interest them enough to open your message. So how do you write a subject line that successfully achieves that goal? Here are seven tips that will help you write an effective email subject line.

1. Keep your email subject line short and sweet.

Email subject lines should be no more than five to eight words in length. That equates to 40-50 characters. Longer subject lines are likely to be truncated, especially if someone is checking email on a phone. Your subject line should be a preview of the message content and let reader's know what to expect when they open the email. 

It should concisely summarize the main points of the message, so that readers can decide if it's worth their time. You recall the old adage, "If I had more time, I would have written a shorter letter." That applies to the subject line as well. Those few words are the most important you will write, so spend time crafting the best subject line you possibly can.

2. Don’t over punctuate!!!!!!!!!!!!

Readers associate overly punctuated email subject lines with spam, which reduces the chance that your message will be read.


That is a technique spammers use. In fact, you may never see the email subject line because your spam filter might catch that email and send it straight to the junk folder. All caps is equal to shouting. You don't want to shout your email subject line. That's digitally rude.

4. Test different subject lines to see what works best.

Many email service providers allow for what is known as A/B split testing. That means you can send one version of an email to one segment of your list and another version to a different segment.

5. Create a sense of urgency.

Include a call to action in your subject line. People may be more inclined to open an email if they feel they're missing out on a valuable opportunity by not doing so.

6. Send a test message to staff members.

Get a few members of your staff to act as guinea pigs and send two versions of the email to them asking which subject line incites the most response.

7. Review reports from previous emails.

Email marketing is a "learn by doing" proposition, and that's where reports come in. Reviewing reports from previous email campaigns will help you determine the types of subject lines that work best. Take what has worked in the past and emulate it in future campaigns. Successful email marketing starts with attention-getting subject lines that make readers want to open your message. 

Bonus Content: How to write open-worthy subject lines

Include numbers

In the era of the listicle, marketers can be assured that lists attract attention. "5 Ways to…”, "These 6 Things are Ruining…”, "10 Puppies Who…”, you get the picture. In a world where massive amounts of info compete for our attention, people are attracted to easily digestible chunks of information (a fact which also informs design and formatting choices).

If your content can be presented as a list, it may make sense to do so. The formality of your subject matter is another consideration here—people already mock some major content sites for their use of this trope, so heavy or serious subject matter will not fit.

Use the 5 "W’s” (and 1 "H”)

Journalists are trained to ask who, what, when, where, why, and how. Consider using these words in your headlines to explain what’s happened up front. If you can summarize or explain the content of the article in a sentence, those interested in the subject matter will be more likely to want to learn more.

"Here’s How a 13-Year-Old Kid Made $20,000 in One Day”
"Meet John Q. Public, the Man Who Runs the Internet”
"What Your Business Needs to Drive More Leads” (rhyme bonus)

These headlines prepare the reader for the article/page in a conversational style.

Share a secret

Everyone loves secrets! Even the word itself conjures salacious feelings—knowing something others don’t gives one a feeling of power, and people enjoy the advantage of having privileged information.

Look at the multimillion dollar marketing concept "The Secret”. Its success lies in its promise to reveal the hidden information and methods that unlock a happy life for the reader— a premise which is irresistible to those feeling the pain the book/movie addresses.

"The Best-Kept Secret to a Happy Marriage”
"Secret Methods for Closing Deals Over the Phone”

Don’t you want to get the scoop on this powerful and mysterious info?

Teach the reader

Many searchers are looking for information on how to solve a problem they’re experiencing, or on how to do something better. Reach out to these people and let them know you’re there to help them gain the knowledge they crave. Help the reader learn how to do better.

"Learn How to Write Headlines that Convert”
"Learn the Secret of Motivating Bored Employees”

Compounding techniques? Now we’re getting somewhere.

Use pathos

Sometimes tugging at your readers’ heartstrings can encourage them to dive into your content. Consider the story of a child who donated his life savings to a family whose house burned down.

"Boy Donates to Needy Family”
"Young Philanthroper Learned it From Dad”
"7-Year-Old Gives Everything to Help Grief-Stricken Family”

One of these three headlines really turns up the emotion and positions the kid as a hero. Emotional headlines work especially well in the case of human interest stories, or for fundraising or humanitarian causes or services.

If your business is not using email to communicate with customers and prospects, you're missing out on one the most tried-and-true marketing tactics the Internet has to offer. Contact us to learn how we can help you get started.