Do Symbols in Subject Lines Increase Performance?

The usage of symbols (such as hearts and stars) in subject lines has definitely been on the rise in recent months. Recently, Paul (Litmus co-founder and CEO) forwarded one I hadn’t seen before: a coffee cup!

Tonx subject line with coffee cup symbol

Used in the subject line of an email from Tonx, a coffee bean delivery service, it caught his eye and was certainly appropriate given the context.

Temporary lift or lasting impact?

Paul’s email reminded me of a brief conversation I had via Twitter recently:

Twitter conversation

I’d been wondering the same thing Loren was. While there’s definitely potential to see an increase in open rate when using symbols in your subject line, does this tactic have lasting impact? In other words, are senders using symbols in subject lines seeing more clicks and conversions in their emails, or just a temporary spike in opens? Anecdotally, I’ve heard that open rates are about 10-15% higher for emails that used a symbol in the subject line, but additional metrics have been somewhat elusive.

(Extremely limited) user research

Curious, I asked Paul, “Did it make you want to click, or just open?!” Paul’s response:

“In all honesty I didn’t even read it after I opened. I did really like it though…”

Chad White at The Retail Email Blog says,

“While we haven’t seen conclusive lift from using symbols in subject lines, it is a tactic to consider.”

Brand attribution and email’s reach

These comments also got me thinking about brand awareness, and how that might be impacted by an intriguing email. Even if Paul didn’t read or click inside Tonx’s email after opening it, you could make an argument that Tonx might be top of mind, at least for a little while. Can Tonx’s email (and creative subject line) prompt a purchase, even though it wasn’t read? After seeing (but not reading or clicking) that email, would Paul be more likely to choose Tonx for his next coffee purchase, since the brand stood out to him recently?

It’s quite possible. AlchemyWorx monitored the timing of non-email related sales and overlaid those figures with the timing for emails sent, finding that non-opened email can have a greater impact than you might think—they call it the Nudge Effect.

“Customers often buy a product or service through another channel within 24 hours of receiving an email”

While their research didn’t mention the effect of including symbols in subject lines, it certainly gives reason to hope that this trend may have the potential to play into something more than just a higher open rate.

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  • http://waldowsocial.com DJ Waldow

    Funny. I was just reading the Bronto blog post about this very topic. I am in including them in tomorrow’s Waldow Social Weekly email. I was able to sneak in a link to this blog post too!

    In fact, I tried to put in a few symbols in tomorrow’s newsletter, but every time I tested them, the symbol was replaced by a question mark. Reading it in Gmail. What am I doning wrong?

    • http://www.litmus.com Justine, Litmus

      Awesome! Thanks, DJ! It’s definitely a trend that’s been written about a lot recently.

      I’ve been doing some tests to explore rendering as a follow-up post. From what I can tell so far, it looks like it may depend on your ESP and how the emails/subject line have been encoded. Can you specify UTF-8?

      • http://waldowsocial.com DJ Waldow

        Yeah. I was thinking it may be ESP specific. As you know … I’m using Infusionsoft (client). However, I have another client using Bronto, so I may have them test it out there. Looking forward to that follow up post about rendering. Seems on-brand for Litmus. Ha!

        • http://www.litmus.com Justine, Litmus

          Definitely on-brand! Let us know what you find out.

    • Adam

      Check the charset — probably looking for UTF-8 — in your EMS’s settings.

      • http://waldowsocial.com DJ Waldow

        Good call, Adam. I’ll check that out.