Data and views from the Consumer Insights & Targeting team at Experian Marketing Services

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Are symbols in emails a risky business?

Symbols in email subject linesSymbols in email subject lines
Unicode data

I recently received an email from a London-based company that I usually engage with regularly but the subject line of this particular message had me clicking straight on the delete button:

“It’s Friday. Can we have a cocktail now?”

The use of symbols in email subject lines is a tactic that’s certainly on the rise – but when it goes wrong, it goes wrong in style. As we can see here even the use of the simplest ‘symbol’, in this case a rogue apostrophe, can have unappealing consequences if this does not translate to an appropriate format for a particular email client. So why take that risk?

Email has become increasingly popular with consumers over recent years; almost 70% of respondents to a recent Experian survey said they favoured email over any other marketing channel. As the number of marketing emails sent increases, brands today must ensure that their emails are tailored and personalised to encourage the recipient to open and engage with the content. Our research shows that using symbols in subject lines is a great way to increase open rates and improve engagement, when you get it right.

But what do we mean when we say “symbols”? Well, every font set (like Arial and Calibri) is made entirely out of “symbols”. Each letter, number and punctuation mark you’re reading right now is a “symbol” in that font set. Many font sets include extra symbols beyond letters, numbers and punctuation. These special symbols, like hearts and stars, are based on the Unicode computer industry standard character set, and are different from images. This Unicode data is encoded in a number of different ways for your computer to store and understand it, and then in turn rendered on your screen using a font to show you the stylised end product. As we see with the marketing email I received earlier, this coding failed to translate for my email client, resulting in a messy delivery of rogue symbols.

For example, a flight operator might use a plane symbol to draw attention to their latest last-minute flight deals, or a cafe chain could use an image of a coffee cup in their subject line advertising their latest range of lattes. You can find a list of Unicode symbols on Wikipedia.

Symbols are a great way to draw in the eye and vary the messaging you regularly deploy to your subscribers. Research from our global client base shows that symbols help to keep their interest up and to spark interest in those that were previously unengaged.

Tips, tricks and considerations when using symbols in an email campaign

Testing, testing…
As with most email tactics that span across clients and devices, there are a few instances in which certain tactics translate differently. For example, some symbols are actually converted from their character form into an image – both the iPhone and Hotmail render a few different symbols as actual images instead of characters.

The best way to know if a symbol will render is simple – test it. Since email providers use different font sets and understand different encoding methods, there are millions of possible permutations of symbols that will render and not render. At the bare minimum, you should be testing your most important groups of subscribers. So, if you know that most of your subscribers read their emails in Gmail or Hotmail, at least view tests in those places to make sure most of your subscribers won’t see the dreaded “empty rectangle” or question mark.

Symbols should make sense
As well as rendering, symbols need to resonate in the context of your emails. A heart in a subject line about a credit card balance might not make sense. The same subject line rules still apply when using symbols – the more relevant they are, the more subscribers will understand and enjoy them.

Keep it fresh
Like all of the best email marketing campaigns, you need to keep a close eye on your techniques and analyse your open and click through data to ensure your campaigns are working. If you test using symbols in your subject lines and see great results at first that taper off, perhaps the “newness” of this tactic is waning. Try testing new symbols or testing symbols against no symbols and remember, the most important thing to your campaign is the receptiveness of your target audience.

We’re often asked if symbols affect your chance at landing in the inbox. The short answer here is no – ISPs and email clients now tend to use engagement data to determine whether a message is spam or not. If symbols work well for your brand and garner higher open rates, then they could, in fact, improve your deliverability. When customers are more engaged with your emails, many ISPS calculate a lower risk that your emails are spam.

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