Symbols in Subject Lines: The Good, The Bad and The Ugly

A new feature to test: symbols in your email subject lines!

The technique of putting symbols in your subject lines is all the rage: more and more big brands are taking the plunge. Some articles covered this topic earlier this summer. I have noticed, however, that Hotmail, which was recently replaced by Outlook, has reacted by adding symbols and integrating color!

Look at the inbox below: ZoneAlarm’s email has a serious advantage over the others, don’t you think?

You can’t see anything besides the email from Zone Alarm. More precisely, you see nothing besides their “call to action”: your eye is immediately drawn to it and your brain does the rest. I don’t have any statistics, but I would be willing to bet their opening rate find itself improved. The role is more limited for Gmail clients. Here is the same subject as it appears in Google Mail:

There’s no more color; only the form remains. The effect is still there, but it’s more subtle. Note that the same thing happens in Yahoo, for example. The situation is also different with smartphones. Here is what it looks like on the iPhone:

But even if the symbols are nicer looking, they are less flashy, and thus, more discreet. The subject does not attract attention in the same way.

A matter of email client

Everything depends on the email service used by your recipients. What service does your audience use to read their emails? This is the question to ask. Some lists are composed of 30 to 40% Hotmail addresses. In this case, it is strongly recommended to conduct a little test, at least on one segment of the list: there may be a lot to gain from this. Otherwise, if your targets use email services that interpret these symbols in black and white, like Gmail and Yahoo, the effect will be more limited, so it is up to you to find out.

Your open rate isn’t everything

Obviously, beside the fact the your open rate is a relative metric (images must be displayed), it should be noted that this indicator is not necessarily related to conversions. Using symbols will be useless if the content of the email is not excellent: the click rate should always be maintained. If the content is uninteresting, or even aggressive, the recipient might be so irritated by the pressure to click that he feels victimized. In this case, he will not hesitate to click the “report as spam” button. A spam rate, however small, is the beginning of the end for your deliverability.

And where does deliverability come into play in all this?

It is always necessary to test, as usual. If possible, try and compare your Spam Assassin scores, which all good email services should provide. But apparently, there’s some good news: these symbols do not seem to necessarily impact the deliverability of your messages. So really, why not try it?

Specifically, how do I proceed?

  • Test and test again. Beyond deliverability, make sure that the symbols render well. Except for Outlook 2003, this should not cause major problems but you never know, and faux pas often happen without warning.

  • You can choose to segment by FAI: why not send emails with special symbols for Hotmail addresses? If they work well, why not?

  • To avoid fumbling and to take advantage of interesting signs, simply copy and paste the symbol, beginning with a nice gallery like this one.

Elie Chevignard

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Digital Marketing Manager at Mailjet.

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