Field notes
Choosing lookback windows that campaign managers can defend
How the length of your attribution window changes which paid and organic touchpoints get credit — and how to explain that choice in a budget meeting.
Campaign managers often inherit a thirty-day or seven-day lookback without knowing who chose it. That silent default shapes every channel contribution table you present.
A short window favors channels that sit close to conversion — typically branded search and retargeting. A longer window pulls earlier discovery touchpoints into the story, which can raise the apparent value of upper-funnel social or display.
Before you change a window, write down the business question. If leadership asks which spend closed last month’s sales, a shorter window may be honest. If they ask which channels started valuable journeys, you need a longer view and clear caveats.
In practice, we recommend publishing two contribution tables side by side for one reporting cycle. The comparison teaches stakeholders that attribution is a framing choice, not a single absolute score.
Document the window in the first page of every report. Campaign managers who can state the lookback aloud rarely get blindsided in review meetings.