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How to write better email subject lines

How to write better email subject lines

Your email subject line is enormously important.

Get it right, and you get to have a few more moments of the recipient’s attention. Get it wrong, and you’ll either get ignored, archived or marked as spam.

What constitutes an effective email subject line?

What should you include? And what should you avoid?

Let’s look at a few solid strategies for writing email subject lines that entice people to open and read.

Some of these approaches are contradictory and many of them don’t work together.

In most cases, it’s best to pick one approach for each email. Over time, you should develop a picture of what your audience responds to, and you can gradually become more adept at sending emails that get opened.


It’s rarely a good idea to use a long subject line, because the end of your line may get cut off by the recipient’s email program.

Subject lines of 4-7 words are the most effective – probably because they are easy to scan and because they stand out against more long-winded subjects. The shorter your subject, the easier it is for customers to understand the offer.


With just a few words available, you can’t skirt around the issue. Every word must earn its keep. Be more like Hemingway and less like Shakespeare. Get to the point. And then stop.


Generalisations and vague promises are not very appealing. If you’ve got something good to offer, be specific about it. Let people know what they’re missing out on.


A sense of urgency is a simple way to get more clicks. If people know they have a limited time to take advantage of a deal, they are far more likely to take action. Don’t abuse this trick though – and make sure there is a genuine reason for time-limiting your offer. This approach makes use of the scarcity principle of persuasionthat we recently wrote about.


We’ve all done it. We've all clicked on a strange email just so we can resolve the mystery.

People like to have their curiosity tickled, but again, make sure you can back this up with a satisfying resolution, otherwise your recipients will just feel duped.


Can you name-drop in your subject line?

If you can mention a recognised person, brand or authority, then people will be more likely to open your email (assuming the authority is relevant, respected and interesting). Anything that can add credibility to your emails will also increase your open rates. This ties in to the authority principle of persuasionthat we recently wrote about. 


Adding the recipients name, recent orders or other preferences is a sure-fire way to get their attention.

Tell it straight

Good emails are bold and confident, without being hyperbolic. Over-selling your offer is a bad idea as it diminishes trust. You may get a short-term boost in open rates, but your once-fooled customers won’t fall for your tricks twice.


Sent the right message at the right time, and you will get a great response. You might want to set up auto-responders around contract renewal times, or send a voucher to customers one week after their first order. How can your emails build on your other activities and maintain momentum?


Use the active voice, rather than passive, to make your subject lines more engaging and clear. The active voice tends to reduce word count – so this is helpful on two fronts.


Can you offer your list an offer that’s not available anywhere else? If you can cultivate a sense of exclusivity within your email list, and make people feel that they get the benefits of membership, they are more likely to act on your messages.


While it’s usually the best idea to focus on positive messages, sometimes it’s good to flip the script and lead with a problem. This can be effective if you know your list well and are confident that the problem you can solve is a problem they experience – and want to resolve.

Do you have any secrets for increasing your email open rates? 

If you want help sending more compelling customer communications, talk to our friendly team. Our customer communications management platformmakes it easy to send brilliant messages to any platform. Why not ask for a demo?