Apple’s iOS 27 blocks ad tech in Safari. What it means for your campaigns.

The topic sounds technical. The consequences are not. iOS 27 arrived in mid-September 2026. With the update, Apple introduced a blocklist in the Safari browser. Certain advertising and data companies are now shut out completely on updated iPhones and iPads. If you are responsible for budgets or run campaigns, this affects you. Not everywhere and not immediately, but noticeably. We explain what is confirmed, what is still open and what you should do now.

What Apple changed

iOS 27 has been available since 14 September 2026. Since then, Safari has blocked a number of advertising and data companies completely. The browser no longer sends requests to these companies. As a result, they can neither collect data nor deliver ads.

One point surprises many people. On the iPhone, every browser runs on the same Apple technology. So the block does not only apply in Safari. It also applies in Chrome and in every other browser on the iPhone.

The list is not public. Companies end up on it without advance notice. According to several trade media, it is likely to keep growing.

Programmatic buyers are hit hardest

Programmatic advertising, meaning the automated buying of ad space in real time, is hit hardest. The large buying platform The Trade Desk was temporarily unable to serve any ads in Safari on updated devices. Providers of alternative identifiers such as LiveRamp, ID5 or Permutive are also blocked. These identifiers replace third-party cookies, which have not been available on the iPhone for some time.

For you, this means less reach on Safari and, in some cases, money spent on ads that were never seen. According to AdExchanger, some agencies report paid impressions on iOS 27 that were never delivered. This is not yet a widely documented figure. As a warning sign, it should still be taken seriously.

Relief is in sight for The Trade Desk. In a test version of iOS 27.2, Apple removed the platform from the list again. But this version is not yet available to everyone. The other providers remain blocked for now. This is the situation as of October 2026.

Google and Meta: the ads run, but the numbers no longer quite add up

The good news first. Your campaigns on Google Ads and Meta continue to run normally. Google DV360 also appears not to be affected at the moment. This has not yet been confirmed conclusively.

The real problem is measurement. Safari restricts access to click identifiers, referrers and cookies. As a result, conversions from iPhone users tend to be under-reported. In practice, your reports show fewer purchases or enquiries via Safari than actually took place. If you only look at the platform figures, you underestimate the contribution of the iPhone.

An open question: click identifiers

Experts disagree on one question. Will Safari soon remove Google and Meta click identifiers (gclid and fbclid) in normal browsing as well? These identifiers link a click to a later purchase. If they disappear, attribution becomes even less precise.

According to the most reliable tests, this is not the case today. In normal Safari mode, the identifiers still work. But Apple has already tried removing them in test versions. And anyone who manually sets the protection to cover all sites has already lost the identifiers. So the direction is clear. The step has not yet been taken.

App advertising: new tracking prompt in the EU

There is a change in the EU for app campaigns. From iOS 27.2, apps in Germany, France, Italy, Poland and Romania must show a new tracking prompt. Users can be asked again one year after their last answer. The new dialogue drops the word tracking and the warning symbol. This could improve consent rates in these countries in the medium term. The sources only mention EU countries. Whether Switzerland is affected cannot be derived from them.

New requirements for ad creatives? No.

As things stand, there are no binding new requirements for ad creatives because of iOS 27. You do not need to adjust or produce anything new.

What you should do now

• Have your conversion tracking moved to the server. This is the most important measure, and all sources agree on it. Measurement then runs through your server instead of the browser. Safari cannot block it. In concrete terms, this means the server interfaces of Meta, Google, LinkedIn and Microsoft. Your tech team or your agency knows which ones these are.
• Have Safari and iOS reported separately in your reports. Otherwise the effect disappears in the average, and you notice too late what is shifting.
• Plan for less reach on Safari in programmatic. If your campaigns rely on third-party identifiers, you reach fewer people on the iPhone. Take this into account in your budget and targets.
• Do not rely on click identifiers alone. UTM parameters still work. Google also has its own helper identifiers for the iPhone (gbraid and wbraid).
• Manage expectations internally. Performance via Safari tends to be underestimated in platform attribution. You should know this before anyone cuts the iPhone share of the budget. And Apple can change the rules at any time without notice.

Conclusion

In most cases the ads keep running. Measuring and targeting via Safari become harder. The effect is still small today, because only a few devices have been updated. But it grows with every update. If you switch to server-side tracking now, you will be in a calm position when the next tightening comes.

Frequently asked questions about iOS 27 and Safari