How to write subject lines that get your marketing emails opened

There's reams of advice out there on how to write subject lines that lead to sky-high open rates. Fiona reckons it all comes down to these five basics.

How to write subject lines that get your marketing emails opened

(This article originally appeared in Radix’s August 2013 email newsletter. If you’d like to receive articles like this once a month, sign up for the newsletter here.)

I’m obsessed with subject lines; those fragile little snippets of copy that hold the key to getting your emails opened.

The power of the subject line is incredible. If a prospect deletes your email because the subject line didn’t appeal to them, the whole opportunity is wasted.

On the other hand, if the subject line intrigues them into opening the email, most of your work is already done. They’re already engaged and interested; all you have to do now is present the case for downloading your ebook, signing up for a free trial, or whatever you’re offering.

Five tips to improve your open rates

So how do you craft a subject line that stands out from the mass of other emails in the inbox and piques enough interest to get your recipient to open the email and investigate further?

There’s a huge amount of advice out there, covering everything from optimum subject line length to whether it’s OK to use symbols and all caps. But essentially, it can be boiled down to five basics:

1. Clearly show the value of opening the email. In its Definitive Guide to Engaging Email Marketing, marketing automation vendor Marketo says that an email should do one of four things: solve a problem, save the prospect money, make the prospect smarter or entertain them. If the subject line can promise at least one of those things, it’s got a good chance of being opened.

email subject line 1

Fast Company’s email leaves you in no doubt that you’re going to learn something useful.

2. Be specific. In Copyblogger’s ebook Email Marketing: How to Push Send and Grow Your Business, Brian Clark says subject lines should aim to be four things: useful, ultra-specific, unique and urgent. If you can’t manage all four, he says, at least go for the first two.

What does specific mean? It’s not enough to offer information on how to ‘be more productive’ or ‘cut costs’, or even ‘tackle the problem of BYOD’. Those benefits are too generic; lots of other emails offer them too.

Instead, your subject line needs to promise a very specific benefit that will justify opening it, and which – ideally – your recipient can’t get elsewhere.

email subject line 2

SlideShare offers some very specific, informative content about how to start a presentation.

3. Use emotive words. Chris Lake of Econsultancy has an interesting blog post about what kind of words ‘work’ in blog headlines to encourage people to click through to read, and the same words can easily apply to email subject lines too. Broadly speaking, it seems that people are interested in how to do things really well (hence ‘mindblowing’, ‘kickass’, ‘awesome’) and how to avoid doing things really badly (hence ‘lousy’, ‘horrific’, ‘fails’).

email subject line 3

Fast Company (again) uses the emotive word ‘insane’ to pique curiosity.

4. Be friendly. As discussed in point 1, your prospects are looking for emails that will solve a problem they have, increase their knowledge, save them money or entertain them. If you can do any or all of these things in a friendly way, it amplifies the sense that you’re on their side. Being friendly is a no-brainer: no one likes to be patronised, bossed about or addressed in soulless corporate-speak. (Just be careful not to be over-familiar, because that can be a huge turn-off.)

email subject line 4

Econsultancy scores a hat trick with a subject line that’s useful, emotive *and* friendly.

5. Keep your word. Don’t have your subject line promise something the email doesn’t deliver. That might work once, but afterwards it will destroy your prospect’s trust in your brand. As Adestra’s Parry Malm says in the firm’s 2013 Subject Line Analysis Report:

“If you use the subject line “Free Beer!” then guess what? You’ll get a huge amount of opens. But unless the contents of the email actually pour your customers a beer, then you’ll have achieved nothing but short term response gain and long term brand harm.”

If you’re keen to read more on this topic, all the reports and blog posts linked to in this post have lots more tips and are highly recommended – just beware of information overload!


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