B2B SaaS sales cycles are routinely 30–180 days. PLG trial-to-paid conversions can take 7–30 days, and the LTV view that actually justifies your CAC can take 12–24 months to fully mature. If your attribution window is shorter than your sales cycle, your reports will systematically misattribute deals that started outside the window — usually crediting them as direct traffic or brand search.
How to pick a window
Pick a window that mirrors the question you’re answering, not a single global default. For weekly campaign optimization decisions, a 7–30 day window keeps the signal fresh enough to act on. For quarterly pipeline reviews and CFO-facing ROAS reports, choose a window that covers at least 75% of your average sales cycle.
For PLG cohort and LTV ROAS work, the lifetime window is the only honest answer. Anything shorter cuts off the recurring revenue that justifies the spend in the first place.
- 7-day: Meta and TikTok in-platform optimization decisions
- 30-day: Google Ads optimization, weekly channel reviews
- 60–90 day: Quarterly pipeline reviews, board reporting for SLG
- Lifetime: PLG cohort LTV ROAS, executive scoreboards
Compare windows side-by-side
The most useful diagnostic is to look at the same report at two different windows simultaneously. If a channel’s revenue grows substantially when you extend the window from 30 to 90 days, that channel has long-tail conversion lag — almost always a top-of-funnel awareness channel that deserves a different ROAS benchmark than your bottom-funnel channels.
Cometly lets you set window per report or per dashboard, so you can run a 'fast' optimization dashboard and a 'true' performance dashboard against the same underlying data.
What to watch for.
- Picking a window shorter than your sales cycle
Half your closed-won deals will fall outside the window and look like direct traffic. Set the window to at least the median deal cycle.
- Switching windows mid-quarter
Comparing this quarter (30d) to last quarter (90d) is meaningless. Lock the window for trend reports.
- Using lifetime windows for daily optimization
Lifetime is too noisy for short-term decisions. Reserve it for executive ROAS and LTV reporting.
Recap.
- Use 7–30 days for paid media optimization decisions inside the platform
- Use 60–90 days for SLG pipeline reporting that mirrors the average sales cycle
- Use a lifetime window with linear attribution to value top-of-funnel awareness
- Compare two windows side-by-side to find the channels with long-tail conversion lag
- Set the default window once at the workspace level so reports stay consistent