Write a winning email subject line

When your email arrives in your subscriber’s inbox, there are two things that straight away impacts the likelihood of it being read. These two things are

  • the identity of the sender in the “from” field, and
  • the email subject line.

As for the “from” address – keep it simple and recognisable with your company name. But how do you write a subject line that will get your email opened?

First we’ll take a step back, and look at how a poor subject line can even prevent your email from reaching your subscribers’ inboxes in the first place.

Words that trigger spam filters

Many of these are obvious – Valium, Viagra, Rolex, Casino – you get the picture. There are a whole bunch of others though that you may be unaware of, and these may get you pipped at the post.

  • Bonus
  • Earn $
  • Double your
  • Do it today
  • All new
  • Congratulations
  • Guaranteed
  • Act now!
  • Instant
  • Urgent
  • All natural

Hubspot have published a comprehensive list of spam trigger words if you’re interested in finding out more words to avoid. Use of CAPS or excessive exclamation marks can also get you sin-binned. Depending on which program you use to send your emails, you may be able to test your email in spam filters before you send it. If you send your emails through Orion Creative, we can do that for you.

Words that repel

Less serious than words that trigger spam filters, yet still undesirable, are the words that have been shown through email testing to seriously hamper the open rates of emails. Help is one, the abbreviations RE: and FW: are others.

Words that work

Ok, enough of all the DON’Ts. What about the DOs? Results from the Adestra Subject Line Analysis Report 2013 (available to download) demonstrates that certain words are currently performing better over others.

For example, Alert, Bulletin and News beat both Newsletter and Report hands down. Sale is more appealing than Save. The word Daily is preferred over Monthly. Video is deemed much more exciting than Webinar. Free Delivery is another popular inclusion (of course use only when relevant!). 

If you’re sending emails B2B, you might also consider Breaking, Editor, Update, Weekly or Trial – all words which increased open rates compared to average.   

Although don’t lean too heavily on these. Aside from notification emails which can benefit from fairly standard subject lines (eg Your connection [insert name] has endorsed you), a fresh subject line can be useful for each email you send. Therefore, if you overuse any of these words, as will can lose their impact over time. It’s more important to create concise, relevant and engaging email subject lines which communicate the particular message of your email.

Be concise in your email subject line

Whether it’s a notification or a newsletter, subscribers want to know what the email is about, in order to be able to make a call on whether they want to read it. A subject line fulfils the role of a personalised headline – giving the key thrust of the communication with an angle to appeal to the reader.

There’s no room to beat about the bush in an email subject line – say what you need to say straight up. Either keep the subject line short, or put the most important information first. This is particularly important with so many subscribers now viewing emails on mobile devices.

Be relevant

While a subscriber may open an email with the subject line ‘Like a free holiday?’, unless the email content follows up with a relevant promotion giving subscribers a chance to do just that, then they may feel misled. You don’t want a subscriber to open an email, only to click on the unsubscribe link!

A/B Split Testing

Sending two identical emails with two different subject lines – and then comparing open rates – can be a very handy way to see what resonates with your subscribers.

And if after all that, your email goes unread in some of your subscribers’ inboxes, at least your email subject line will be read – one more reason it should encapsulate what it is you really need to say.