Do emojis in subject lines increase open rates?
TL;DR
One emoji in a subject line is roughly neutral, sometimes a touch positive. Two is the ceiling. Three or more drags opens down and trips the same density signal that buckets bulk mail. The bigger story is the niche split: B2B SaaS and finance lists do worse with any emoji, while ecommerce and lifestyle tolerate a single leading one. Position beats count, and the count past two is where it goes wrong.
Do emojis in subject lines increase open rates? A little, sometimes, in some niches, and the number everyone quotes to prove it is wrong. If you have read three blog posts on this, you have read the same 56 percent stat three times, usually followed by a shrug and the line "but test it for yourself." That is not an answer. Here is one, built from the subject lines we score every day rather than a press release from a decade ago.
We run a subject-line model on a large corpus of real newsletter sends, and emoji use is one of the things it measures. So we can say more than "it depends." We can say where it helps, where it hurts, and by roughly how much.
Why the famous 56 percent stat is misleading
The number you keep seeing comes from an Experian study, recycled since around 2018, that reported brands using an emoji in the subject line saw a 56 percent higher unique open rate. It gets pasted into Mailchimp roundups, agency posts, and SendPulse explainers as if it settled the question. It did not.
Two problems. First, it compared brands that chose to use emojis against brands that did not. That is selection, not a controlled test. The kind of brand reaching for a party popper in 2018 was usually a consumer brand with a younger list and a marketing team willing to experiment, so the emoji was riding on top of a dozen other differences. Second, it measured unique opens, and unique opens have become a soft metric since Apple Mail Privacy Protection started pre-fetching images and inflating the figure. A 56 percent lift in a number that no longer means what it meant in 2018 is not something to plan around.
The honest version is less exciting. The real effect of a well-placed single emoji is small. It is not zero, and in the right niche it is positive, but it is nowhere near a coin flip on your open rate.
What our subject-line corpus shows
When we bucket subject lines by emoji count, the pattern is a shallow curve, not a ramp. Zero emojis is the baseline and it is fine. One emoji sits right around baseline, sometimes a point or two above it depending on niche. Two emojis is the practical ceiling. Past that, the line bends down: three or more emojis scores under 40 in our model and the open rate in the corpus follows the score down.
The same pattern shows up in our seven-factor subject-line model, where emoji density carries 10 percent of the weight. It is a real factor, but it is the fifth or sixth most important one, well behind the opening verb and the length band. People obsess over the emoji because it is visible and fun to argue about. The model says spend that energy on the first word instead.
Position turns out to matter more than count. A single emoji at the front of the line ("Save 30% this weekend") draws the eye as the inbox row scans top to bottom. The same emoji wedged into the middle breaks the reading rhythm and tends to score lower. An emoji at the end is usually safe as long as the words ahead of it are carrying the message. So if you are going to use one, lead with it or trail it, do not bury it.
Score your subject line before you hit send
The subject line tester runs the same emoji-density and opening-verb checks on any subject in your browser, and tells you in one line where it is losing points. Want a head-to-head? Run two versions through the subject A/B battle.
Open the subject line tester →The niche split nobody mentions
Here is the part the recycled stat hides by averaging everything together. The emoji effect is not the same across niches, and in one big slice of the market it goes negative.
In our corpus, B2B SaaS and finance senders do worse with emojis. Subject lines with any emoji averaged a few points below the no-emoji subject lines from the same senders. Not a cliff, but consistent enough that we stopped treating it as noise. The reason is reader expectation. Someone subscribed to a security product's changelog or a fintech briefing reads a rocket emoji as a consumer-marketing tell, and it quietly undercuts the credibility the rest of the email is trying to build. The emoji is not offensive, it just signals the wrong category.
Ecommerce, lifestyle, media, and creator newsletters are the opposite. A single leading emoji fits the register there and costs nothing, sometimes helps. Readers of a deals newsletter or a food publication are not surprised by a flame or a fork and knife, and the emoji can do a little work pulling the eye to the line. This is the audience the 2018 Experian brands mostly came from, which is another reason the stat looked so strong.
So the rule splits cleanly. If you sell to businesses, drop the emoji and put the effort into a stronger opening verb. If you sell to consumers, one leading emoji is fine, two is your limit, and the choice matters less than you think. We keep watching people in B2B add the rocket because a blog post told them emojis lift opens by 56 percent, and we keep seeing it not pay off.
Do emojis trigger spam filters?
One emoji almost never lands you in spam on its own. The trouble is density and company. A subject line with three or more emojis is rarely just three emojis: it usually arrives with an exclamation mark or two, a word like FREE, and an over-capitalised phrase. Filters score on the stack, not the single signal, so the emoji becomes one more weight on a message that was already leaning promotional. That is the same density logic we cover in the piece on how spam filters actually work: no single feature blocks you, the combination does.
There is a second cost that has nothing to do with filtering, and it is the one people forget. Emojis do not render the same everywhere. Newer glyphs, skin-tone modifiers, and combined sequences can fail on older Outlook builds and some corporate clients, and when a client cannot draw the character it shows a tofu box, the little empty rectangle. A subject line that reads "Your weekend deals" on Apple Mail and "Your weekend deals box-box" on a locked-down Outlook desktop looks broken to exactly the reader you most wanted to impress. The newer or rarer the emoji, the higher that risk.
The tradeoff is real even when an emoji helps a little. You buy a small attention edge in the inbox and you take on a rendering gamble plus, in the wrong niche, a credibility hit. For a single common emoji at the front of a consumer subject line, that trade is worth it. For anything past that, it stops being worth it fast.
How to test emojis on your own list
None of this replaces your own data, because your audience is not the corpus average. The way to settle it is a clean A/B test: same send, same time, same content, the only difference being the emoji. Split a meaningful slice of the list, send version A with one leading emoji and version B with none, and read the open rate after a full day so late openers count.
The catch most people miss is sample size. Open rate differences from emojis are small, often a point or two, and a 500-person split will not tell a real effect from random wobble. You want enough subscribers per arm that a two-point gap is outside the noise, which for most lists means thousands per version, not hundreds. If your list is small, run the same test across several sends and pool the results rather than trusting one. We walk through the mechanics in the guide on running a subject-line A/B test, and it is worth getting the setup right before you draw a conclusion you will repeat for a year.
One more habit worth building: watch what works for the competitors in your niche. If you want to see whether the newsletters you respect use emojis and how often, tools like MailCharts and the alternatives we compare here let you read subject-line patterns at scale without subscribing to fifty lists by hand. Pair that with your own open-rate baseline from the open-rate benchmarks and you will know whether the emoji question is even where your gap is. Often it is not.
Frequently asked questions
Do emojis in subject lines increase open rates?
Marginally, and only in some niches. In our subject-line corpus, one emoji is roughly neutral to slightly positive, two is the ceiling, and three or more drags open rate down because it reads as promotional noise. The widely quoted 56 percent Experian figure came from comparing brands that adopted emojis, not a controlled test, so it overstates the real effect.
How many emojis is too many in an email subject line?
Three is too many almost everywhere. Zero or one is the sweet spot, two is tolerable in consumer niches, and three or more scores under 40 in our model and trips the density heuristic that Gmail and Outlook use to bucket bulk mail. If you are counting past two, cut back.
What is the best emoji for email subject lines?
There is no single best emoji. Position matters more than choice: a single emoji at the front of the line outperforms the same emoji wedged mid-subject. Pick one that renders cleanly across Apple Mail, Gmail, and Outlook and that matches the message, then stop. Decorative emojis that have nothing to do with the content read as filler.
Do emojis trigger spam filters?
A single emoji rarely does. Density is the problem. Three or more emojis stack with other promotional signals such as ALL CAPS, exclamation marks, and urgency words, and push a message toward the bulk or promotions bucket. Emojis also carry a rendering risk: clients that cannot render a glyph show a tofu box, which looks broken in the inbox.
Should B2B emails use emojis in subject lines?
Usually no. In our corpus, B2B SaaS and finance subject lines with any emoji averaged a few points below their no-emoji peers from the same senders. The audience reads emojis as a consumer-marketing signal, which works against a tool that wants to look credible. Drop the emoji and put the work into the first verb instead.