This article is part of a series that answers newsletter questions we often hear from users. Send us any questions you'd like to answer!

Email newsletter open rates are a half-truth, at best.

Most email apps report nothing back to the software that sent the messages. The only way to get data out of email apps is for the user to take action.

Open rates run on the idea that when someone opens your email, the email app can download an image and subsequently log every time that image was downloaded. That’s obstructed, though, by people who read offline, and more commonly by email apps that either block remote images (hurting open rates) or pre-load all images (artificially inflating them). Good open rates hover around 30% today (ranging low twenties to upper thirties from a variety of studies) and lower than 10% open rates are cause for concern. But again, you can’t fully trust them.

Click rates run on the idea that servers can track when someone clicks a link in your email. They’re a more accurate email interaction stat, though can still be artificially inflated by email apps and spam filters that automatically open every link in email to check for malicious content. Consider them directionally accurate. Mid-2% click rates are common across a number of surveys, and lower than 1% click-throughs are cause for concern.

Reply rates are based on the number of replies an email newsletter receives. They’re the only reliable stat in email. They’re also something you’ll need to track manually, if replies come into your personal email app, or may be able to opt into tracking via your newsletter platform. But public statistics on good or average response rates are rare, as by default they’re not tracked. The more, the better.

With that comes the nuance.

Lies, damned lies, and open rates

The idea behind email open rates started in the late ’90s, as HTML email became default and messages could fetch images from remote servers. The server hosting the image could then count every time the image was loaded, compare that to the total number of emails sent, and voilà, open rates.

Yet almost as soon as what we’d come to call tracking pixels was popularized, their effectiveness was curtailed. Image servers didn’t only see that someone downloaded the photo, they also saw the person’s IP address, operating system, locale, and more—details every website can see when you load their pages, but enough to feel invasive in something as private as email.

Microsoft Outlook led the charge, blocking remote images by default in 2003, instantly excluding a portion of your audience from “open” rates. Gmail took the fight in another direction, serving images via “Google’s secure proxy servers” starting in 2013. Apple implemented a similar strategy with Mail Privacy Protection in 2021, preloading all images locally.

That doesn’t mean you shouldn’t pay attention to open rates. It does mean that you should take them with a hefty grain of salt.

By default, no Outlook reader will show up in your open rates, and every Gmail and Apple Mail subscriber will look like they faithfully open every single email you send. Since Apple Mail is used by 46% of email readers, and Gmail another 24%, over 70% of average subscribers may automatically show up as having read your newsletter.

And, as expected, average open rates have gone steadily up over the past few years, as more users upgrade to email apps that automatically fetch images. Campaign Monitor saw 21.5% average open rates in 2022, while SendGrid in 2023 saw an average of 19%, with only the top 75th percentile seeing over 25% open rates. Today, MailChimp reports a 36% average open rate, while Mailerlite’s average is as high as 43%.

It’s safe to say that you should see 30% open rates, today, for a newsletter with average engagement and a reasonable mix of subscriber demographics. It’s also safe to say that open rates, today, tell you less about how your subscribers behave and more about how their email app behaves.

The only time to worry about open rates is if they’re unusually low in today’s pre-loaded image environment. Google says it does not track open rates, and that “low open rates aren’t necessarily an accurate indicator of deliverability or spam classification issues.” At Buttondown, we watch only for statistical outliers, and expect newsletters to see at least a 10% open rate.

Click-Through Rates: The most reliable default email stat

Click tracking relies on the same concept as open rates: Whenever someone clicks a link in an email, the website server can log the visit. Click tracking can be more detailed, too, with UTM data that can identify the paragraph where the link was clicked and the specific subscriber who clicked the link. It’s also universal; most email newsletter providers like Buttondown redirects links in your email through short, trackable links to track clicks to any link in your newsletter, to your or others’ sites.

It’s still not perfectly accurate. Some spam filters and security tools automatically open every link to check for malicious content; those could show up as false positive clicks. But for the most part, click data is real—and that shows up in the average stats. Unlike open rates with their privacy-driven inflation, average click rates have held steady or even gone down over time.

SendGrid in 2023 said that “click rate is an extremely strong indicator of engagement,” and saw an average 4.48% click rate. Campaign Monitor’s 2022 study found an average 2.3% click-through rate. Mailchimp and Mailerlite in 2025 found 2.6% and 2% click rates, respectively.

You should, on average, expect 2% or better click-through rates for newsletters with average engagement and content style. This, of course, will vary drastically depending on your newsletter style; an email that includes the full content will get fewer clicks than one that summarizes a blog post then includes a link to continue reading (we have found, though, that email length doesn’t affect your click rate). And, in the same vein, you could boost your click-through rate quickly with a clickbaity title—and lose your reputation and hurt your long-term click rate in the process.

Don’t over-index on click rates. Even with their better accuracy, see them as a directional indicator. “A sudden drop in typical open and click rates may also indicate there are deliverability problems,” notes Mailgun as one reason to keep an eye on click rates, regardless of newsletter type. As with open rates, Buttondown flags click rates under 1% as problematic.

Response Rates: The most human metric

Since open rates are likely to be wrong, click rates may be lower for certain types of emails, and some readers may love your emails but never click through to your site, using either open or click rates to track engagement can be problematic. The one true indicator of email enthusiasm? Replies.

“The email gods and goddesses love a reply,” as Buttondown founder Justin Duke writes about the reply loop. And you, as a newsletter publisher, should love replies even more.

Replies show not only that someone opened and read your email, but also that they liked (or disliked, even) it enough to take the time to reply. That proves a hundred times more interest in your newsletter than an open (which, odds are, is fake) or click (which could be an unintentional tap). It tells you which emails got the most excitement and what things your readers care about most, and tells the reader’s email app that emails from your domain should be prioritized as much as those from their boss and significant other.

The only problem is, replies are often not tracked. By default, replies go to your personal inbox, and your email newsletter service is none the wiser. And while some newsletter apps, including Buttondown, now include opt-in reply tracking, public data on good or average reply rates is rare. What's good is entirely up to you and your audience.

You can track things on your own, if you’d like. Search your inbox for Re: with your email newsletter’s name, or use a unique replyto: address so every reply goes to a special inbox or gets logged with an email automation. Or, opt into reply tracking, if that’s an option. Buttondown includes opt-in reply tracking, which adds a Buttondown email address as the replyto: address in your email newsletters, and then both forwards replies to your personal address and shows them along with comments and mentions in your notification inbox.

You’ll have some noise in the data, and might need filters to remove auto-replies and out-of-office messages from the stats. But with a bit of care, you’ll be able to track your average email reply rate over time; up and to the right should be good, unless everyone’s emailing to complain.

Then keep an eye on the stats. Make sure your open rates aren’t dropping through the floor, that your click rates are averaging 2% or better, and that replies are growing over time. See what people respond to, and double-down on that. And one issue at a time, you’ll build an email newsletter with enviable open and click-through rates, if only it was possible to accurately measure them.