Email opens have never been an incredibly accurate metric.
Tracking pixel-based opens is deflated by image caching, image blocking, and email clients that don't render images, such as voice assistants and smart watches.
Moreover, they're inflated by pre-fetching—most notoriously by Apple's Mail Privacy Protection (MPP), which seeks to obscure real user opens by burying them in a tsunami of auto-generated opens.
The launch of MPP two years ago immediately led to cries of "Opens are dead!" But much like the cries of "Email is dead," they should be ignored.
That is doubly true if you're a B2B marketer, because you're likely to be less affected than your B2C counterparts.
However, MPP has changed how marketers can and can't use opens. Understanding those changes starts with understanding...
How Your ESP Reports Opens
Some of the confusion around the reliability of opens is a result of email service providers' (ESPs) not being transparent enough about how MPP has affected their open reporting.
To be fair, it was a confusing time, and Apple sprung the change on everyone. However, many months after the launch of MPP, some ESPs hadn't said anything about MPP—and when some eventually did, it was a whisper in footnotes in their apps.
That's why so many marketers in 2022 were publicly bragging about the great job they'd done increasing their open rates by 50%, 80%, or even 100% or more! They didn't understand it was a mirage courtesy of Apple—a mirage that wasn't dispelled by their ESP.
Today, ESPs handle Apple auto opens in one of three ways:
- Reporting all opens, including auto opens. If your open rates soared in 2022, this is what your ESP did. A sky high open rate may look and feel good, but it's mostly junk data, which makes it difficult to use effectively.
- Reporting reliable opens only. If your open rates declined in 2022, this is what your ESP did. It's the approach that we at Oracle use with our Responsys and Eloqua platforms. Although it means losing the real opens that are obscured in all of Apple's auto opens, it means marketers can use their opens and open rates safely, and in all the ways they did pre-MPP.
- Calculating an adjusted open rate. If your open rates were largely unchanged in 2022, this is what your ESP did. When calculating the open rates for your campaigns, it simply ignored your subscribers who were generating auto opens, basing the open rate solely on the open rate generated by your non-MPP users (or similar calculations). The upside of this approach is that your historical open rates remain useful, but the downside is that the rate is less accurate and can give you the false sense that you have reliable opens for way more of your audience than you actually do.
If you're unsure which approach your ESP is using, do some investigating. Also, determine whether your ESP makes it possible to break out auto opens from MPP users and reliable opens from non-MPP users. For example, Oracle strips out auto open from our reporting in Responsys and Eloqua, but we allow customers to access auto open data for their subscribers on an individual level, should they want to.
To calculate an adjusted open rate yourself, you just need to know the percentage of your audience that's enabled MPP (they're the ones generating auto opens) and the open rate among your non-MPP audience. Then you can extrapolate your non-MPP open rate across your MPP audience. It won't be perfectly accurate, but open rates never have been.
If you don't have access to that data and you're stuck with inflated MPP open rates, then it's time to establish new open rate benchmarks. MPP adoption peaked more than a year ago, so year-over-year open rates should be quite stable now. That means the data now allows you to understand whether your recent campaigns are doing better or worse compared with last year.
Four Ways Opens Are Still Useful
Access to reliable opens makes all of the following use cases easier. Even if you have access only to opens that include auto opens, you can still get value out of them.
With the first three use cases, changes in your open rates can be just as telling as what your open rate actually is. Regardless of how your ESP reports opens, you'll be able to use those changes to draw conclusions.
1. Understanding Campaign Engagement
Especially if you're a B2B, media, or consumer brand company, all of your email campaigns aren't trying to drive sales. At least some—perhaps even most—are trying to drive brand engagement, retention, or lead-scoring efforts. Along with clicks and website activity, opens are a key measure of those.
2. Measuring Click-to-Open Rates
Comparing the ratio of openers to clickers allows you to understand two things:
- How aligned your subject line is with the body content of your email
- How effective your body copy is at driving clicks
If your click-to-open rate is lower than usual, first check to see whether your subject line is vague or misleading. If it's clear about what subscribers can expect to find when they open your email, then the email's body copy is likely not pulling its weight.
3. Seeing Major Deliverability Problems
When you've been blocklisted or you're suffering major deliverability problems at an inbox provider, that will be clearly visible in your open rates—especially if you're able to break down your open rates by inbox provider. Unless you're working with a deliverability monitoring service, that is probably the best way to recognize significant deliverability issues.
4. Managing Subscriber Inactivity
... At least for your non-MPP users. Opens are still the best way to qualify subscribers as safe to mail, so use reliable opens to measure subscriber engagement when you have them.
When you don't, you'll need to use email clicks more heavily. You may also want to factor in the recency and frequency of a subscriber's purchases, Web visits, app use, and other activities when considering whether a subscriber is active or not.
How Open Rate Use Has Changed
All of that said, MPP has fundamentally changed some aspects of email marketing that relied on opens.
1. Subject Line Testing and Subject Line Optimization
Prior to MPP, open rates were routinely used to judge the success of subject lines and almost universally used to drive subject line recommendation engines. That was unfortunate because most brands don't want their subscribers to merely open their emails; they want them to engage on a deeper level, which open rates don't always predict well, particularly if the subject line is vague or overly clever.
Because of MPP, subject line optimization engines have incorporated clicks into their algorithms and marketers are relying much more on clicks for their subject line testing as well.
For me, that is one of the few silver linings of MPP, which has otherwise made it much harder for brands to serve their subscribers well and satisfy inbox providers by sending to engaged subscribers only.
2. Send Time Optimization
Similar to how subject line optimization engines adjusted their algorithms post-MPP, send time optimization engines have done the same. The benefits have been similar because brands don't just want to send campaigns when they're likely to be opened, they want to send when subscribers are likely to have the time to engage more deeply. Clicks are a better signal for that.
The downside is that clicks are a far less frequent signal, so send time optimization engines are now slower to react to changes in the engagement times of individual subscribers. That said, send time optimization still produces far better results than using a universal send time, unless you're a high frequency sender.
3. Open-Triggered Journeys
Long a common device among B2B marketers, email journeys wherein an open in the previous message triggers the next is no longer viable. Although marketers have a variety of alternatives to drive those journeys, none of them are great substitutes.
* * *
MPP absolutely makes it harder for email marketers to manage their programs responsibly and serve their subscribers well, but opens are alive and well.
Apple has now come out with Link Tracking Protection (LTP) in Safari, so the next thing you'll likely hear are cries of "Clicks are dead!" You should ignore those, too.
LTP will have a much smaller impact on email marketers than MPP did. In fact, LTP will probably have a negligible impact on most email marketers.
More Resources on Email Open Rates
How iOS 15 Will Kill Email Open Rates—And How Marketers Can Prepare
Beyond Open Rate: Eight Metrics for More Effective Email Marketing
