How an Attribution Window Decides Which Touchpoints Get Paid

What is an attribution window?

Marketing teams set an attribution window, the lookback period inside which a touchpoint can still receive credit for a conversion. Any touch older than the window gets deleted from the conversion path before the attribution model runs, so the window decides which rows exist and the model decides only how to divide them. Check the window on both reports before comparing them, because identical session data produces different channel totals under different windows.

The window is a filter, not a weighting rule. A marketing attribution model splits 100 percent among the touchpoints in the path; the window decides which touchpoints are in the path at all. Single-touch rules are just as exposed: first touch under a 7-day window credits the oldest touch inside that week, not the real first touch.

How does the same conversion split at a 7, 30 and 90 day window?

One conversion pays two, three or five channels depending only on the window length. Take a single $1,800 purchase with five touchpoints, split under linear attribution, and change nothing but the lookback period.

Touchpoint	Days before purchase	7-day window	30-day window	90-day window
Organic search, blog post	84	0%, $0	0%, $0	20%, $360
Google Ads click	41	0%, $0	0%, $0	20%, $360
LinkedIn ad click	22	0%, $0	33.3%, $600	20%, $360
Newsletter click	5	50%, $900	33.3%, $600	20%, $360
Direct visit, checkout	0	50%, $900	33.3%, $600	20%, $360

Read the newsletter row left to right: $900, then $600, then $360. The LinkedIn row climbs from $0 to $600 and falls back to $360 as four other channels dilute it. Nobody edited a campaign, a tag or a budget to move these numbers.

A short window does not only lose revenue at the edges, it pushes the same revenue toward whatever ran closest to checkout, which flatters retargeting and paid brand search and starves multi-touch attribution of the early touches it measures.

How do you check whether a touchpoint falls inside the window?

A touchpoint qualifies when the gap between it and the conversion is no larger than the window. The test runs once per touch, before any model math:

eligible if (conversion timestamp - touchpoint timestamp) <= window length

The LinkedIn click sits 22 days before the purchase. Under a 30-day window, 22 is not greater than 30, so it survives alongside two other touches, and each of the three takes 100 / 3 = 33.3 percent, or 0.333 x $1,800 = $600. Under a 7-day window, 22 is greater than 7, the row disappears, and the two survivors split 100 / 2 = 50 percent, or $900 each. The $1,800 never changes. Only the denominator does.

The same deletion moves conversion rates too: dropping touches changes which sessions get labeled paid, which changes the numerator in the conversion rate formula for every channel you report.

The eligibility test, one touch at a time

1

Log the timestamp. Record a timestamp for the touchpoint and for the conversion.

2

Compute the gap. Subtract the touchpoint timestamp from the conversion timestamp.

3

Compare to the window. Check whether the gap is no larger than the window length.

4

Keep or drop the touch. A touch inside the window enters the path; a touch outside it is deleted before the model runs.

What is the difference between a click-through and a view-through window?

A click-through window measures time from an ad click, and a view-through window measures time from an ad impression that produced no click. Ad platforms run both and add the results into one conversion number, which is why platform-reported conversions include people who never clicked anything. View-through windows are short because an impression is weak evidence; click-through windows are long because a click is recorded intent with an identifier attached. Google Ads adds a third, the engaged-view window, which starts from a video engagement.

What are the default attribution windows in Google Ads and Meta Ads?

Google Ads defaults to a 30-day click-through window, a 1-day view-through window and a 3-day engaged-view window, while Meta caps its standard click-through window at 7 days and its view-through window at 1 day.

Platform	Click-through	View-through	Engagement based
Google Ads, default for a new conversion action	30 days	1 day	3 days, engaged view
Google Ads, configurable range	1 to 90 days, by conversion source	1 to 30 days	1 to 30 days
Meta Ads, standard attribution setting	1 day or 7 days	1 day	1 day, engage-through

Google's "About conversion windows" help article states the 30-day, 1-day and 3-day defaults and the 1 to 90 day range for Search and Display, read on 8 September 2026. Meta's Business Help Center article "About attribution models and attribution settings" lists 1-day or 7-day click-through, 1-day view-through and 1-day engage-through for website and in-store conversions, read on 8 September 2026. Confirm both in your own account, because platforms change defaults without changing the article title.

Why do your ad platform and your analytics tool report different numbers for the same campaign?

The two systems apply different windows to different evidence, so they answer different questions about the same purchase. Google Ads counts a conversion inside a 30-day click window and a 1-day view window against its logged-in identity graph, Meta counts one inside a 7-day click window and a 1-day view window against its own graph, and your analytics tool counts sessions on your domain, sees no impressions at all, and rebuilds the source from the landing URL. One order gets claimed by both ad platforms and split again by analytics, which is why platform conversions sum to more than your order count.

Identity widens the split. Ad platforms match a click on a phone to a purchase on a laptop through account login, where a domain-side analytics tool sees two anonymous visitors, and links shared without UTM parameters arrive as direct traffic while the ad platform still claims them. Flowsery records the campaign source on each session through UTM campaign tracking and reads settled payments through revenue attribution from Stripe, Paddle, Polar and Lemon Squeezy, so the amount being divided is the amount that cleared. Reconcile against the payment processor, not a platform dashboard.

How long should your attribution window be?

Set the window past the median days from first touch to purchase in your own data, then round up to the nearest platform option. Check the 90th percentile as well as the median, because a window at the median cuts the long paths, and the long paths are where the top-of-funnel channels sit. Google's "About conversion windows" article points at its own time lag report for this measurement, read on 8 September 2026.

Median days to purchase	Window to set	What a shorter window costs you
Under 3 days, impulse ecommerce	7 days	Almost nothing
10 to 25 days, considered purchase	30 days	Paid social and display credit
Past 30 days, B2B or high ticket	90 days	Organic search and content credit, entirely

Once the window is set, hold it. Google's "About conversion windows" article documents that a change applies only to conversions recorded from that day forward and never backfills, read on 8 September 2026, so every change puts a seam in your history. Change it once, on purpose, and annotate the date.

Frequently asked questions

Does a longer attribution window increase reported revenue?

A longer window increases the number of credited touchpoints, not the revenue. The $1,800 order stays $1,800 at 7, 30 or 90 days, spread across more channels, so per-channel revenue in the closing channels drops. Conversion counts on ad platforms do rise, because a longer window catches conversions that fell outside the old cutoff.

Which attribution window does Google Analytics use?

Google Analytics 4 runs its own lookback windows, set in the property's attribution settings, separate from the conversion windows configured in Google Ads. That separation is one reason the same campaign shows two conversion counts inside two Google products. Check the property setting instead of assuming it matches.

What is a view-through conversion and should I count it?

A view-through conversion is a conversion recorded after someone saw an ad without clicking it, inside the view-through window. Treat it as a directional signal for awareness campaigns and keep it out of cost-per-acquisition math, because the same purchase gets claimed by the click-based channel that drove the visit. Report the two in separate columns so nobody adds them by accident.

Why does a longer attribution window not fix missing touchpoints?

The window controls how far back you look, not what was recorded. Cross-device journeys, ad blockers, private windows and links pasted without campaign tags remove touchpoints before the window applies, so widening the lookback on an incomplete path credits a longer stretch of the same gaps. Fix collection first, then tune the window.

Should the click and view windows be the same length?

No. A click is intent tied to an identifier and a view is an impression that carried no action, so the two carry different evidence and deserve different windows. Google Ads and Meta both pair a 1-day view window with click windows of 7 to 30 days, which is the ratio to start from.

Can I compare two campaigns that ran under different attribution windows?

Not directly. Rerun both reports under one window before comparing them, because the earlier numbers came from different eligibility rules on different sets of touchpoints. Where a platform will not backfill, compare orders and revenue from your payment processor and treat the platform numbers as ranking signals.

Are touchpoints outside the attribution window discounted or removed entirely?

Touchpoints outside the window are deleted from the conversion path before the attribution model runs, not given a smaller share. In the $1,800 order example, the organic search touch at 84 days scores $0 under both the 7-day and the 30-day window, because the row never reaches the model. The same touch only enters the split under the 90-day window, where it earns $360 alongside the other four channels.

Can Google Ads use a different attribution window for each conversion source?

Yes. Google Ads' configurable range runs from 1 to 90 days and can be set per conversion source, while the platform default stays at a 30-day click-through window with a 1-day view-through window. Meta's standard setting caps the click-through window at 1 or 7 days across the account, without that same per-source range. Check each conversion action rather than assuming the account default covers every campaign.

What does Google Ads' engaged-view window measure?

The engaged-view window is a third window type alongside click-through and view-through, and it starts counting from a video engagement instead of a click or an impression. Google Ads defaults this window to 3 days. It applies to video ad formats specifically, since it tracks engagement with the video rather than a static impression.

Why do Google Ads and Meta conversion counts add up to more than my actual orders?

Each platform applies its own window and its own identity graph to the same purchase, so one order can get counted twice. Google Ads counts a conversion inside a 30-day click window and a 1-day view window against its logged-in identity graph, and Meta counts one inside a 7-day click window and a 1-day view window against its own graph, independently of Google. Reconcile against the payment processor instead of adding the two dashboards together.