Email subject lines: the long and the short of it?

Email subject linesBack in the good old days of the late 1990s we were always taught that business email subject lines should a) be very short and b) never use the word “free” as this would instantly confine the mail to the recipient’s junk folder. Now, though, it appears this isn’t quite the case any more.

Even the dreaded word “free” no longer, necessarily, strikes anger into the heart of email junk folders; according to current sources, the word “free” is still one of the most powerful in email marketing and gets through as it deserves to.

“Though it’s true that long subject lines may still not be fully visible in many email client viewers, their content itself is rarely ever cut off or truncated. Research done by Alchemy Worx, a London-based email service provider (ESP) a few years ago, found that long subject lines are powerful motivators of not only opens but also clicks. Long subject lines, then, are better relevancy indicators than short subject lines,” says a recent article on my alma mater website,

So, long, short, or what?

Despite measurement metrics being the schizoid lunacy that they are, IMHO, the research suggests some rather weird notions – supported, however weird, by substantial evidence. Boiling it all down, here is my interpretation:

Short subject lines of up to 60 characters have high open rates, but don’t have very high click-through rates. In other words people may be captured by the short come-on sufficiently to look further, but once into the email aren’t interested any more.

Long subject lines of 70 characters or more, provided that they encapsulate your offer enticingly, may provide slightly fewer open rates, but apparently lead to far more click through rates to your ultimate sales message, so it seems.

“Long subject lines also allow for the inclusion of multiple (vs. single) topics when email messages contain multiple offers or benefits” continues the MarketingProfs article. “Such more descriptive subject lines better set and manage the recipient’s expectation of the email’s contents; accordingly, they correlate to higher email response rates vs. merely email opens.”

There’s a “dead zone” – why?

The research done by Alchemy Worx shows that there is no happy medium between the quick in-and-out of the 60 character subject line and the much longer variety. In fact, there is a “dead zone” on subject lines of between 60 and 70 characters which leads to a relatively insipid response either in terms of pure opens, or opens leading to clicks through.

According to Alchemy Worx, responses happen with subject lines of up to 60 characters, or of more than 70 characters, but with very little in that yawning gap between. Interesting? Yes, I thought so too.

And Suze’s take on it all?

Definitely intriguing, and gratifying up to a point. However I’m not yet convinced that spam / junk and other filters cheerfully accept the use of the word “free.”

Beyond that, it’s comforting to know that email recipients are, perhaps, prepared to read longer subject lines to see what might be in it for them.

But come what may with business email and email marketing, we had better make sure that we smack ‘em in the teeth with a very, very worthwhile offer of what’s in it for them whether we’re counting 60, 120, 240 or however many characters in the subject line.

Online marketing metrics may change, but human nature doesn’t.

What do you think?  

More help to get those emails right every time:

“How To Write About Yourself”…how to make the most of yourself, whatever you need to write

“Business Writing Made Easy…everything you need to know about writing for business in English




  1. My two cents:

    As someone on a lot of different people’s email lists, I can tell you the last thing I’m wanting is to get pitched. Sure, I’ll buy a product if it looks helpful, but if I’m being pressured into it, 9 times out of 10 (or 10 out of 10 for that matter) I will go the complete opposite direction, regardless if it looks helpful or not.


    • I think there’s a big difference between a hard pitch, and a subject line that tells you “what’s in it for you,” Ashley. I agree, the glaring, blaring “buy this today or your b*lls will drop off” sales approach is not only pushy, but also downright insulting to potential purchasers. A line that tells it like it is without shoving it in your face is, for me anyway, far more effective. Thanks for stopping by!

  2. Thanks, Suze, for this really useful post! I think the e-mail provider has a lot to do with whether the message ends up in spam. I pay money for aweber because of the service’s high deliverability, and I think it’s worth the dough.

    And now, thinking about my own e-mail behavior, I can see that I am very likely to open messages that give me lots of specifics in the subject line.

  3. Another useful blog – thnk you Suze. The subject line is so important – the rest of the email could be pure gold, but if the headline doesn’t entice them, it will end up deleted anyway.

    To be honest, ‘tho, with some emails I’ll open (or delete without reading) because of who it’s from rather than what the subject line says.

    • Interesting point, Jane – advertisers can’t help being who they are, unless of course they adopt spammers’ habits and send information under some fake name!

  4. Unless that headline speaks to me, I am not going to open the email regardless of the headline length. I have noticed the uptake on the FB trend to put the site name or initials in square brackets. I find that very annoying.

    • Exactly, Sarah. That’s just common sense. The statistics from the Alchemy Worx report are interesting all the same, although what they found was that the more informative, long subject lines worked better overall – which tallies with your comment about a headline having to “speak to you.” Very short headlines/subject lines are hard pushed to “speak to you” in any meaningful way.

  5. I don’t look at the length of email newsletters I get or send. I believe that having a subject line that gets someone to open what you send matters. Then you have to make sure the content is good AND expands on what the subject line said.

    • Absolutely, Trudy. Common sense prevails here, and at the end of the day length of subject line SHOULDN’T matter, but it seems – according to the statistics, and to what extent can we trust those? – length of subject line does make a difference in some quarters, anyway. Weird.

  6. Well… funnily enough I was talking about this just this evening in a teleclass.

    If your list is used to getting regular and frequent emails from you and they KNOW they are going to get interesting, engaging and informative content, then your subject line doesn’t matter much at all, really.

    Much MORE important is you From: header. It should be your name, so they know who’s writing to them.

    And what’s really interesting is people are talking about open rates (which you can’t measure accurately) and click through rates (which you also can’t measure terribly accurately) and not sales — and really sales is all we ought to care about.

    What would you prefer?

    A 99% open rate and 1 sale?

    Or 1% open rate and 10 sales?




  1. […] may remember my article a few weeks ago in which I shared some interesting statistics about open rates for business/marketing email based […]

  2. […] Blog post at How To Write Better : Back in the good old days of the late 1990s we were always taught that business email subject lines should a) be very short and b) never use[..] (Email subject lines: the long and the short of it?  […]