Facebook Ads announced today it’s retiring its 28-day attribution window option. After they do, the longest remaining attribution window will be their already-existing 7-day option.
Why the Change?
According to their official announcement sent directly to advertisers, “Upcoming digital privacy initiatives affecting multiple browsers will limit business’s ability to measure people’s interactions across domains and devices. Among those limitations is the ability for businesses to attribute conversion events back to an ad over longer attribution windows.”
The email does not cite the specific privacy initiatives causing the change.
“Upcoming digital privacy initiatives affecting multiple browsers will limit business’s ability to measure people’s interactions across domains and devices. Among those limitations is the ability for businesses to attribute conversion events back to an ad over longer attribution windows.” – Facebook’s official announcement
The email also explains this will make advertising more “resilient” for future privacy and browser changes. Though they don’t explicitly say it, this likely referencing Chrome’s intention to eliminate third-party cookies in the next two years.
Chrome’s initial steps were going to be taken in the spring, but were delayed due to Covid-19.
When Will the 28-day Window Be Gone?
The changes take effect October 12th, in just a couple weeks. All historical data is available until that date. Facebook recommends advertisers download any relevant data tied to the 28-day attribution model prior to that date.
Understanding 28-day Attribution’s Role In Your Account
If advertisers use the standard attribution window for Facebook, that will affect their future results. By default, Facebook has used a 28-day click attribution model unless an advertiser changes it to 7-day or 1-day.
Advertisers can use the “compare windows” feature to get a sense of how heavily their results skewed towards the 28-day mark. This is an option towards the bottom when a user chooses to customize their column view:
Clicking on it displays the option to choose the attribution window, along with comparing it to the default window:
Update Rules Tied to 28-day Attribution
If advertisers have any automated rules that rely on the 28-day attribution model, those should be updated.
This is particularly true for any rules regulating spend and budget based on 28-day performance. Once gone on October 12th, the rule will revert to the 7-day model. This could impact spending.
Does This Apply to the Facebook Ads API?
Yes, though they will not enforce it on October 12th. As a workaround, the API will continue to supply the 28-day attribution data until the browser limitations officially hit.
Facebook stresses the 7-day attribution model is a more realistic view of ad impact, downplaying the role or weight a 28-day attribution should be given. (Interesting, given that its been their default for so many years.)
The Future of Privacy & Ads
As privacy measures continue to move forward, there will no doubt be future changes.
Advertisers are also recently feeling the pinch from the disappearance of search query data by Google Ads recently, with brands bracing for what the future will mean for their paid ads.
Many will continue to watch Facebook even more closely, as their history of issues surrounding privacy measures have been the most visible to the public.