How Apple’s latest anti-tracking update ITP 2.1 will impact your data

Inflated numbers of users in your reporting (Google Analytics, Adobe Analytics et al), broken attribution modelling, shrinking behavioural marketing audiences and skewed A/B test results are some of the big changes to expect, but there is more.

Understanding how ITP 2.1 (beta) will impact your digital marketing efforts will need some attention over the next few weeks, so let’s start at the beginning.

Apple have announced the release of an updated version of its Intelligent Tracking Prevention (ITP) with the latest update to Safari 12.1. The first version of ITP was released in 2017 and aimed to protect user privacy by restricting the ability of advertisers to track people around the web. The technology achieved this by blocking third party cookies which ad tech companies used to target cohorts – groups of users who shared certain behaviours and preferences.

This caused a real problem for advertisers, publishers and businesses who were using third-party cookies to build remarketing audiences but dramatically improved the internet for users – remember those creepy ads that follow you everywhere around the web? Yeah, those...

What is the big change in ITP 2.1 and why does it affect my data?

Advertisers are smart people too, so they started using first party cookies for their targeting.

First party cookies are typically used to measure how users interact with a website and recognise them when they return. By default, a first party cookie from Google Analytics, for example, has an expiry date of two years. Here’s a link if you want to dig into the technical details of it.

With ITP 2.1, first-party cookies will automatically expire after 7 days! This means that a user returning to your website after more than 7 days will no longer be recognised as a ‘returning user’, but be counted as a ‘new user’.

Let’s say, they visit your website three times in a month (with 7+ days between visits), your monthly reporting will show you three unique users instead of one. This has a number of unpleasant ripple effects into various digital marketing disciplines:

How will ITP 2.1 impact my Google Analytics data?

The issue is not restricted to Google Analytics, but affects all web analytics platforms, including Adobe Analytics, Heap etc.. As the update rolls out (expected later in March), you will see an increase of users from Safari which won’t be real, (see above explanation of double-counting users).

For some of our clients, Safari users make up as much as 40% of total users! So, go and check how big the impact will be for you.

Another big impact on your data will be in channel performance and attribution. Safari conversions won’t be attributed to a channel that preceded a visit more than 7 days ago, instead it will now be  attributed to ‘Direct’ in Google Analytic’s default attribution model.

But it is not all doom and gloom. Session-level metrics won’t be affected and your total conversions and revenue won’t be affected either.

How does ITP 2.1 impact my advertising campaigns?

If you are running large scale campaigns or programmatic, we recommend that you speak to your ad tech provider about how this will impact your campaign efficiency.

Audiences and remarketing conditions containing user activity beyond a 7 day period will be impacted by this change. So for example, an audience of existing customers will only recognise users who purchased in the past 7 days.

Also, audiences built in Analytics 360 and pushed into YouTube (via Display & Video 360) will be impacted by this change, because the cookies will be reset just the same.

What’s the impact of ITP 2.1 on our CRO and A/B testing tools?

We work with most of the big platforms and at the moment we believe this change will impact all of them equally. This is because the first-party cookie is used to ensure that a returning user is shown the same test variation / personalised experience they saw during their last visit, if they are on Safari 12.1 or later.

This means that a returning user could end up in another ‘bucket’ and therefore see an entirely different version of the website if they come back after more than 7 days. This will result in a  potentially confusing and poor user experience as well as skewed test results data, neither of which sound great!

Of course, you can segment your test results by browser once you’re done but, with up to 40% of your visitors now seemingly behaving erratically, it may take you a lot longer to achieve statistical significance on your tests.

Will ITP 2.1 have an impact on personalisation?

Yes, probably. This depends of course on the logic that drives your personalisation engine. Real time personalisation, where the user experience is shaped by their behaviour during that very session, won’t be impacted. But recognising the preferences and behaviours when they return will now only work if they return to your site within 7 days.

You might be able to get around it if your users are logging into to your website every time they visit. The options will depend greatly on each case and user journey. To better understand what to expect and how to prepare for it, we have reached out to our platform partners and will update this post as soon as we hear back from them.

So, what can we do about it?

First of all, let’s remember that this change was made to improve the experience of users on the internet in general. We are all about the customer experience here at Fresh Egg, so we won’t advocate any work-arounds at this stage. It is too early to say what will happen next. We expect Google to be working on a solution of some sort, but let’s not forget that ‘work-arounds’ of the ad tech companies are largely to blame for this happening in the first place.

Blaming ad tech companies, Zuckerberg or Brexit may make us feel marginally better for a moment, but let’s start thinking about more practical approaches to the issue:

  • Can your website be interesting enough to get users back once a week?
  • Are users logging in and can we leverage the login details to carry the cookie info across visits?
  • Consider your conversion optimisation efforts – should you be testing across browsers or instead exclude Safari users from certain tests so they don’t skew the overall results? If your site has enough mobile traffic, testing iPhone users in isolation could be another option.

Most importantly, be aware of the change and keep an eye out for when it goes live. Plan for the change, start talking about the impact to key stakeholders across the business and do some more investigation. We don’t have all the information at this stage but wanted to give you an early heads-up.


Since writing this blog post, we have been testing a work-around by our favourite Google Tag Manager geek, Simo Ahava, which captures the Google Analytics cookie information in local storage*. We wanted to know if this was a feasible solution for our clients, so we tested it on the Fresh Egg website. What we found was an unexplained increase in 'direct' traffic from the moment we implemented the fix and it seemed that organic search was the most impacted channel.

Chart showing a timeline of Google Analytics data

To ensure this was caused by the implementation of the work-around and not just a coincidence, we reverted the change. Direct traffic levels dropped back to normal.

The cookies behaved as expected during our testing so we don't yet know what could be causing this, but we are working through the steps of the implementation again to look for possible reasons. As before, we will keep this post updated with our findings.

At the moment, we recommend you be careful with any proposed work-arounds and keep a close eye on your data if you have implemented anything.

* You can explore the complete history of Apple’s ITP tracking functionality updates as well as the details of his proposed work-around here on his blog:

If you want to speak to someone about this then please contact us today. And if you can think of other areas of digital marketing that will be impacted by this, we would love to hear from you in the comments.