Understanding Attribution Windows in Retail Media: How Long After an Ad Should Sales Count?

Common Attribution Windows

Same-Visit Attribution

Credits a sale only if the shopper purchases the advertised product during the same store visit where they were exposed to the ad. This is the most conservative and credible window. Best for impulse categories and in-store audio ads.

24-Hour Window

Credits purchases made within 24 hours of ad exposure, including a return trip to the same store. Captures shoppers who were influenced but didn't buy immediately. Requires loyalty data to track the same shopper across visits.

7-Day Window

The most common window for retail media reporting. Captures delayed purchases and stock-up behavior. Industry standard for many retail media networks including Walmart Connect.

14-Day Window

Used for higher-consideration categories or new product launches where trial may take longer. Less common and viewed with more skepticism by sophisticated advertisers.

Custom Windows

Some networks allow advertisers to select their preferred attribution window. This creates comparability challenges when benchmarking across networks.

Why Attribution Windows Matter

A 7-day window will always show higher sales lift than a same-visit window because it captures more purchases. This makes it crucial to compare campaigns using the same attribution window. An advertiser seeing "15% lift" on one network (7-day window) vs. "5% lift" on another (same-visit) isn't necessarily seeing worse performance on the second network.

Industry Best Practice

The IAB recommends that retail media networks report on multiple attribution windows so advertisers can evaluate performance at different levels of conservatism. At minimum, networks should report same-visit and 7-day results. Transparency about attribution methodology is becoming a key differentiator for retail media networks competing for advertiser dollars.