Facebook Removing 28-Day Attribution Window [Update]

For brands with longer consideration periods or high-ticket items, the switch to a 7-day window could potentially have big effects on how they view Facebook performance.
While platform attribution is a good way to inform trends and optimizations, it can be limiting in terms of providing a full picture of how a channel plays in a marketing mix. Brands and marketers should look to have a more comprehensive and neutral view of performance through an outside attribution model. For more information on how Tinuiti works with clients to provide customized solutions, read more about our Mobius offering.
 
For the affected brands, Facebook recommends pulling all relevant data tied to that model prior to October 12. On top of that, Tinuiti suggests that any advertisers that currently report on a 28-day window should begin optimizing to and reporting on a 7-day window as soon as possible to pull together a baseline for the future. Other things to note: 
 
According to Facebook’s official announcement sent directly to advertisers:
UPDATE FROM FACEBOOK [10/8/2020]:
Looking at the last three months of Tinuiti client performance, roughly 35 percent of purchase conversions fell after the 7-day click window. This decline in attribution could lead to Facebook being underrepresented in a cross-channel measurement.

We previously communicated that we would be introducing a small test to update the default click-through attribution window to 7 days and remove access to the current default of 28 days this month. Taking into account advertiser feedback, we are no longer proceeding with the test for any advertiser in Q4 2020. As a result, advertisers will continue to be defaulted to and have access to the 28-day click-through attribution window in Ads Manager and Ads Reporting through the end of the year.

Original post below:

How will this impact advertisers?

“Upcoming digital privacy initiatives affecting multiple browsers will limit a 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 announced that it will be removing the 28-day attribution window option for some brands from its advertising platform. This window has historically been the default window for Facebook ad campaigns, but after the change, the longest window available will be 7-days.
 
The shift is due to changes browsers are making with regard to cookies, including updates to Chrome and Safari, which already limits first-party cookies to seven days.
 

Next year, we expect upcoming web browser changes may impact our tracking for events across websites. As such, we still anticipate that we will have to shift to a 7-day default attribution window and no longer be able to provide a 28-day attribution window in the coming months, as early as January 2021. If we proceed, we will be providing more details when available prior to this shift to help advertisers like you manage through such a transition.

However, Facebook emphasized in their release that their delivery models don’t rely on a 28-day window, so in theory, there should be little to no impact on campaign performance.

Next steps

 
Despite the 28-day window being the standard window, Facebook emphasized in their release that the 7-day model is a more realistic view of ad performance for the platform. The platform also acknowledges that brands who have been using the standard attribution window can expect a decline in conversions from those campaigns.
 
Tinuiti is recommending that advertisers who have historically relied on 28-day windows should consider running lift tests to find what attribution model makes the most sense long term in the event this rolls out more broadly.
 
Those brands affected will receive word directly within their platform via notification or their direct Facebook rep. Facebook had no update as it relates to the timing of a full sunset of the 28-day window.

    • Use the Comparing Windows feature to see how conversions attributed to your ads compared across different attribution windows. This will allow you to better anticipate any changes in reported conversions as a result of moving to a 7-day window.
    • Update any automated rules currently using a 28-day attribution window to prevent any unexpected adjustments in spend once the new 7-day click-through window default goes into effect.