An attribution window is the lookback period after an ad interaction during which a conversion can be credited to that ad. Click windows (7-day click is common on Meta) and view windows (1-day view) can both count — inflating reported ROAS if finance only recognizes click-through. Align platform defaults with your MMM or incrementality study before scaling.
Shortening windows drops reported conversions without changing actual business outcomes.
Last verified Jun 4, 2026