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6 tips on how to write an effective email subject line

Chances are you receive at least one or two emails every day from various retailers. But how many emails do you actually think are relevant and worth opening? Emails from friends and family need little incentive to open, but emails from a retailer need to provoke enough intrigue to get us to take action right? Writing an effective email subject line is key to getting it opened. But many retailers neglect to spend enough time on this key element of the communication. Of course, any retail business needs to focus on creating great email content to keep us interested, but it’s of little relevance if the recipient won’t even open the email in the first place.

Check out the following 6 tips for writing an effective email subject line for your retail business.

1. Tone test and segment

Some customers prefer succinct facts (20% off sale across all lines). Others like a bit of quirkiness (Did someone say discount? Darn right they did!). While others might respond to something that feels more urgent (Get 20% off for the next 48 hours). So retailers should split test different tones and gradually hone in on what groups of customers respond to more. This approach has the potential to allow you to segment customers by the feel and tone of the subject line, perhaps revealing something of their personality.

2. The Art of Enticement

Remember the subject line needs to be good enough to entice the recipient to open the email. You're pitching to consumers and telling them what they get out of it.  "Get" being the operative word here and a good short one to use to clearly tell the recipient what he/she will get in return for their attention, e.g: "Get X across all orders of Y". It's persuasive and clear and tells me what I get if I do something.

Depending on the service or product being marketed, you might also look to entice someone to open an email by adding a sense of urgency. Offering a limited-time or limited-stock offer can work well and certainly drives footfall into European Discount Stores like Aldi and Lidl. These when its gone its gone promotions can work really well so if you're going to test one, communicate it in the subject line. You could try something like: "Get X only when you shop this weekend" or "Get X today, only Y left. They're flying."

Intrigue can also work to encourage recipients to open an email. If you're rewarding VIP customers you could create a sense of anticipation by saying something like: "You deserve a special treat". Or if you're trying to entice a customer, who is starting to become at risk of lapsing, to come back and re-engage with you, you might try something like this: "We've missed you, and this is how much"

So in summary, play with being persuasive and intriguing. And give the recipient the respect they deserve when it comes to selling in the subject line. Avoid hyperbole and superlatives. It's never the best sale ever in their eyes!


3. Align subject line to segment objective

This is a bit of an obvious one. But we've seen cases where the subject line hasn't aligned to the objective of the email. Retailers who harness their customer data effectively will more than likely have different segments of customers, based on various criteria.

This segmented insight enables the content of the email to be tailored accordingly. But don't forget about the subject line too. Saying a personal: "Thank you Jon Smith" to a very important customer goes down better than "Special discount just for you!". The later is too generic and could be sent to anyone. So just remember if you have a particular segment objective in mind, ensure the subject line aligns relevantly, using appropriate language and tone.


4. Be topical where possible

Combining something that is very current and an element of humour can often work quite well create intrigue. Think about when you're going to send an email, to whom and what's going on in the world (seasonal events, celebrity news, sporting events etc.) that you can create a link with to your brand. At the time of writing this, the Rugby World Cup is about to start in England, so retailers could write something like "Kick of your world cup in style" or "Rugby widow or Rugby fiend?"


5. Be Succinct

It goes without saying that you need to watch the length of your subject line. The number one reason why people use mobile phones is to check email (91% of us check email at least once a day on our phones, followed by 90% who send text messages). Therefore there's only a finite amount of characters to use up within the subject line. As a rule of thumb don't go over 40 characters.


6. Test, test and test again

If you think you've created the perfect email subject line, you may assume that you needs to do no more. But trends change as do customers and indeed devices and the way we use them. So it’s vital that all marketing is monitored across a number of contextual (e.g. most commonly used devices for checking email and the restrictions on those) and performance criteria (e.g. open rate by customer segments). Even the slightest change can be picked up early, which means your business can adapt in real-time with your customer base.

Most of the time testing is done in a fairly ad hoc, last-minute manner. It's almost not worth doing it at all if it isn't a deliberate exercise. So do make some time to plan your tests, use control groups and analyse results in a segmented fashion.