How to Write Email Subject Lines That Get Opened


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An email subject line is like the headline in an ad. It’s the first thing you notice – and the most important part of the entire message. It’s even more critical with email than with an ad.

If someone sees your ad, they may miss or ignore the headline, but be attracted by a photo or a sub-head.

With email, everything else is largely hidden.

If the subject line doesn’t say “open me!,” you’re sunk.

A writing tip from David Ogilvy

Whether in print or online, spend most of your time on your headline. To quote David Ogilvy (who never saw an email but knew a few things about headlines):

On the average, five times as many people read the headline as read the body copy. When you have written your headline, you have spent eighty cents out of your dollar. -David Ogilvy

Good, bad, and ugly subject lines

Here are some sample email subject lines:

Stocks Set to Rebound After Yesterday’s Fall

The problem with this headline is that it tells you the entire story. There’s no need to click and read the entire email. I already know the market went down yesterday, and the headline tells me that they are expected to rise today.

Here’s another take on that same headline:

The Five Stocks That Survived The Market Slide

If the stock market has been sinking, knowing which stocks have retained their value is useful and important information.  Where do I click?

Or, what about this one:

Spark Business with Webinars, Podcasts, and Online Video

Looks like the email is about different ways to market your business.  All good tactics.  The trouble isn’t with the content.  The trouble is that they’ve given away the entire strategy in the subject line.  There’s really no need to read further.  OK, I can use these tools to promote myself, one, two, three, check.  Done.

What if we changed this a bit.  Make the headline say something like,

How to Spark More Business

With that headline,  you won’t know what the tools are unless you open the email.

Here’s another one:

5 Ways to Break the Rules of Email Marketing

It promises I can break some rules, but there’s absolutely no way to tell what I’ll gain by doing it. I also can’t tell whether the rules are legitimate or foolish.  What if, instead, the headline made a promise about how I can be more successful by breaking the rules.  Say something like:

Profit From Breaking Email Marketing Rules – 100% Legal!

Makes you wonder what the rules are, how you can make money, and reassures you that it’s legal (you’re not spamming anyone).  The contradiction between doing something that sounds dodgy, and knowing that it’s perfectly legal gets your attention. You now want to open that email to find out exactly what you need to do to increase your profits.

In each case, the new subject lines work because they engage emotions, tell a story, or promise one.  You can do this by arousing curiosity, creating a mystery, setting up a contradiction, or promising useful information. And that’s why emails with these subject lines get opened.

Got a favorite email subject line? Or a question about writing them?  Ask in the comments.


Which Email Subject Lines are the Best?

The Presidents Cup golf trophyThe subject line of your email is your entry (or quick exit) to someone’s time and attention.  After the list, it’s the most important part of the email.

A good subject line will get your email opened.  A poor one will send it straight to the trash bin (or worse, the spam folder).

Which subject line is the best?

There are quite a few factors to consider when crafting your subject line. How long should it be?  Is shorter better?  Should you personalize it by putting the recipient’s name in each email? Should you be formal? Or write more casually?

Best subject line length

Conventional wisdom says that shorter subject lines are better since they don’t get cut off in phones and tablets. However, Marketing Sherpa recently reported on a Return Path study that analyzed the length of subject lines and compared the subject length to the rate at which the emails were read.

It turned out that longer subject lines had a higher read rate (meaning more people marked it read in their email clients)

Even so, the difference wasn’t big enough to be statistically significant. The takeaway here is not so much to count letters as it is to try to tweak your subject line to get the best response from your own list.

To personalize or not?

As you can see in this more recent Marketing Sherpa article, some industries, such as consumer products, showed a marked increase in both open rates and transactions. For others, such as entertainment, the impact was negligible. Personalization used to work well overall, then it dropped off, now it seems to work well again (at least in some cases). The best approach is to try it and see whether it works for you.

Best email subject lines

As a general rule, show your readers a clear benefit in the first two words. Stay away from hard sales pitches, and include something that invites action or curiosity:

  • Simple Email Change Boosts Sales 55%
  • Text or HTML:  Which Gets More Clicks?
  • Your Copy of Email Open Rate Study Enclosed
  • A simple email marketing formula
  • The Google slap is coming

Try a casual approach

With the latest political season in full swing in the U.S., candidates from both parties are frantically trying to raise money. One side is doing much better than the other.  They test and retest everything, and often find that a simple, “[candidate/celebrity] wants to meet you” or invitation asking readers to join them for an event outperforms more conventional subject lines.

Use emotions and hot button issues

Try a subject line that reacts or references recent news or events, or expresses outrage at something they’ll also find objectionable, “media says I’m to blame.”  Use a call to action to encourage your readers to do something (take advantage of a special offer, buy a new product, pass along something to a friend).

Keep it short (generally)

Top performers are usually short (30-40 characters) and this is usually seen as the ideal length for an email subject line.  However, longer subject lines can work better with a download, such as an ebook or a report.

Worst performing email subject lines

Anything that sounds too pushy, talks about the sender (rather than the recipient), or asks for an action before gaining trust

  • Uh oh
  • Forward this to your friends
  • Big Riches, Small Investment
  • ENDS TONIGHT! Training expires AT MIDNIGHT

The first one is negative and so vague that it’s discouraging. The second one asks you to spam your friends (no thanks).  The third is just plain spammy. The last one looks like it’s shouting at you.

Compare performance

Look at your own data. See which subject lines got the most opens and click-throughs to your sales page.  Also check to see which emails had the highest conversion rate (signups or sales).

If your list is large enough, try a sample of a few thousand names.  Test two subject lines against each other and see which one performs better. Then roll out the winner to everyone else.