How to write winning subject lines for your emails

Working in the email marketing domain, I know just how much effort goes in to crafting the perfect email. You’ve thought about your brand, attractive images, tempting offers and the right message to gain those much needed click-throughs.

So then why do I have dozens of unread emails still in my inbox?

Because the subject line didn’t entice me. You can put everything you have into your email, but if you get the subject line wrong then you’ve gone and fallen at the very first hurdle.

Check out my 7 top tips to writing winning subject lines…

Tip 1: Keep it short

Many studies have been done into the perfect length of an email subject. In fact, Return Path found that click-through rates were 75% higher for shorter subject lines.
When you think about how busy you are while skimming though your inbox, then it just makes sense to have a shorter subject line.

But you also need to remember that mobile device space is limited. And considering 91% of consumers check their email at least once a day on their smartphone – this is not something you should easily dismiss.

My advice? Keep your subject line to no more than 20 – 30 characters and take out any filler words.

Tip 2: Be clear on what you’re offering

When deciding whether to open your email or not, the first thing that people consider is: “So what’s in it for me?”.

They probably have hundreds of other emails clogging up their inbox, so why should they open yours ahead of other brands? Tell the reader what you are offering them so they can make the informed decision to open it.

Many businesses make the mistake of trying to be elusive because they think it will get a higher open rate. Well that might the case, but once they’ve opened it and found out the email is not of interest, you’ll end up in the junk folder – or worse – gain another one for the unsubscribe pile.

So long as you are targeting the right audience, you don’t need to be ambiguous with your message.

Tip 3: Add the personal touch

People love to see their own name in an email subject. Rather than just making it look like you are sending out one big mass email, it shows that you actually have taken the time to find out a little bit more about that customer.

For example: “Dave, we’ve picked this just for you”

A subject line like this will not only help build up rapport with the consumer, but it’s entices Dave to open it!

If you use a CRM software then you can create a profile for your customers and target them with specific emails (even segregated by location) to help improve click-through-rates.

Tip 4: Include a deadline

Putting a deadline on something creates urgency and it will make the reader feel like they have to act quickly, otherwise they’ll lose out. And who likes to lose out, on anything?

Creating a sense of urgency is ideal for subject lines such as sales and discount emails.

Deadlines such as “For 24 hours only..” or “Free shipping ends at midnight..” can really help to not only entice people to open the email, but to click-through because they know exactly what they are getting – and they want it!

Tip 5: Use numbers and lists

In the same way that numbers or lists are the perfect recipe for a blog post title, the same can go for an email subject. Not only is this way of marketing enticing, but lists just make things easier for us to process – which is why we like them.

For example: “6 of the hottest Summer trends..”

This subject line tells the reader that if they open the email, they will be given 6 different style tips. It’s less of a sales-orientated email, and more focused on giving readers advice – which will in turn build trust making the reader more inclined to open your emails in future.

And the great thing about using numbers or lists is that it works for any product!

Tip 6: Get creative and use symbols

Love ’em or hate ’em, there’s no denying that the emoji has taken over our screens. And considering major email clients and mobile devices do support symbols and emojis, it’s definitely worth exploring for your next subject line.

Not sure how to include one in your subject?

Take a look at this blog post we created to find out: How to use symbols on email campaign subject lines.

Tip 7: A/B test for winning results

My final tip is to test your emails so that you can be sure you’re using the most optimal subject line. With a/b testing you can come up with two different options, stagger your senders list to find out which one has a better open rate, and then send the bulk of your emails using the winning subject line.

I’d also suggest taking a look at this tool, SubjectLineGold, as you can use it to predict the results of your campaigns before you send them – and it gives you advice on how to improve your subject lines for the better!


With 35% of email recipients opening an email based on the subject line alone – it’s important to make sure that you get it right. Make sure you follow these 7 top tips and let us know if your open rates improve!

Want to know what NOT to do? Check out our previous blog post: When subject lines go bad.

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