Pro-tip: No emojis in the friendly from

This is one of those things that a client learned about the hard way, so I wanted to share with you all with the hope that you can avoid some of the same pain that they, and I, experienced, while helping them troubleshoot this issue.

Avoid including emojis in the friendly from field.

The friendly from is not exactly a header, but it's part of the from header, the text that goes along with your from email address. (Learn more about what it the friendly from is here.) People love to customize the friendly from to various ends: it could be an effort to drive better recognition of their brand, it could be to suggest a personal connection between sender and recipient, or it could be something done to help drive more sales. Or maybe sometimes you might even modify it just to look cool. That's okay; we've all done it.

But what you should avoid doing is including any graphical characters or emojis. This means no dinosaurs or flowers (or checkboxes, or robots, or faces, or whatever other emojis you can think of). While in theory no ISP is intending to block mail containing the T-Rex emoji next to your from address, what Gmail does intend to block is any graphical characters that could be confused with UI elements -- meaning anything that could conceivably be perceived as trying to trick a user into thinking that the emoji was something official, placed there by Gmail, or part of the Gmail user interface.

How does that affect you? The problem is, you don't know for sure which emojis they're going to block. They don't publish a list, and they won't talk about it. While I did later get an informal confirmation of this behavior, we discovered through testing that a certain emoji in a certain client's friendly from was causing MOST of their mail to be rejected by Gmail, with a very generic "this message looks like spam" response. Not only was the reject message not terribly insightful, not ALL mail bounced! Thus making it extra hard to trace the situation back to this particular character in this particular header. But through a process of elimination and (what felt like) a zillion tests, we did finally figure it out. And so, now, I'm here warning you: If you don't like pain, don't dabble with emojis in the friendly from.

As far as I can tell, emoji in the subject line still seem to deliver just fine (with an exception -- see update at end). I have yet to see any evidence of any big mailbox provider blocking mail because of emoji (or certain emoji) in the subject line. But as always, test and monitor for bounce spikes. (And if you're wondering how to properly encode an emoji into your subject line -- assuming your sending platform doesn't do this for you automatically, here's a neat little encoding/decoding tool from Steve Atkins of Word to the Wise.)

Update: Vytis was kind enough to leave a commend below warning that freenet.de considers emoji in subject line to be a bad thing. Beware, if they're a significant part of your recipient audience.