Google Ads Attribution Windows Explained: Why Your Conversions Don't Add Up
Click-through, view-through, and engaged-view attribution windows determine which conversions appear in your Google Ads reports. Here is how they work and why they cause discrepancies.
Updated 7 min read
Your Google Ads dashboard says 82 conversions last month. GA4 says 64. The CRM shows 71. The answer starts with a question nobody asked: what is the attribution window?
An attribution window is the time period after an ad interaction during which a conversion can be credited to that interaction. Google Ads defaults to 30 days for most conversion actions. A click on March 1st that converts on March 28th counts as a March 1st conversion. Change the window to 7 days and that conversion disappears entirely.
The window you choose determines which conversions exist in your reports. It is not a reporting preference. It is a definition of what counts.
Click-through windows
The click-through attribution window measures conversions that happen after someone clicks your ad. Google Ads typically offers these options:
- 1 day — conversion must happen on the same day as the click
- 7 days — within a week
- 30 days (default for most actions) — within a month
- 60 days — two months
- 90 days — three months
The 30-day default works for many businesses but is wrong for two extremes. For impulse purchases (low-cost e-commerce, app installs), the real decision window is 1 to 3 days, and a 30-day window gives credit to clicks that had nothing to do with the purchase. For long sales cycles (enterprise software, real estate, financial services), 30 days is too short. A prospect who clicks an ad in January and signs a contract in March generates a conversion that falls outside the window.
View-through windows
View-through conversions happen when someone sees your display or video ad, does not click it, and later converts through another channel. Google Ads counts this as a conversion influenced by the ad impression.
The view-through window is separate from the click-through window and much shorter. Options typically range from 1 day (the default for most formats) up to 30 days.
View-through attribution is inherently weaker than click-through. Seeing an ad and later converting does not prove the ad caused the conversion. But it is not worthless either — display advertising works partly through impression effects that click tracking cannot measure.
The practical question: should you count view-through conversions in your reports? If you are running display or video campaigns, yes, but separately from click-through conversions. Blending them into a single "conversions" number inflates the campaign's apparent performance. Showing them separately lets the client see both and decide how much weight to give each.
Engaged-view windows
For YouTube campaigns, Google added a third window type: engaged-view conversions. An engaged view means the viewer watched at least 10 seconds of a skippable ad (or the full ad if shorter) but did not click. If they convert within the engaged-view window (typically defaulting to 3 days), Google credits the conversion to the video ad.
Engaged-view sits between click-through (strong signal) and view-through (weak signal). The viewer demonstrated attention by watching but did not take the direct action of clicking. It is useful for evaluating YouTube campaign effectiveness but should not be mixed with click-through conversions without labeling.
| Window type | What triggers it | Typical default | Signal strength |
|---|---|---|---|
| Click-through | User clicks the ad, then converts within the window | 30 days | Strong: direct intent signal |
| View-through | User sees the ad (no click), then converts within the window | 1 day | Weak: correlation, not causation |
| Engaged-view | User watches 10+ seconds of a skippable video ad, then converts | 3 days | Medium: attention without action |
Why Google Ads and GA4 disagree on windows
Even when looking at the same conversions from the same campaigns, Google Ads and GA4 report different numbers. Attribution windows are one of several reasons.
Different default windows. GA4's default attribution lookback for paid channels is typically 30 days for clicks and does not count view-through by default. Google Ads defaults to 30 days click-through and 1 day view-through. If the Google Ads number includes view-through conversions that GA4 ignores, the Ads count will be higher.
Different attribution dates. Google Ads attributes a conversion to the click date. GA4 attributes it to the conversion date. A click on March 1st that converts on March 20th is a March 1st conversion in Google Ads and a March 20th conversion in GA4. Over a full month, the totals may be similar, but daily and weekly counts diverge. For a full walkthrough of all the reasons these numbers differ, see our GA4 vs Google Ads discrepancy guide.
Different models. Google Ads' data-driven attribution and GA4's data-driven attribution are different implementations. Google Ads' model looks only at ad interactions. GA4's model looks at all traffic sources, including organic and direct. A conversion that Google Ads attributes entirely to a search ad might be split between paid and organic by GA4. For more on how these models work, see our marketing attribution models explainer.
Choosing the right window
Match the window to the buying cycle. The attribution window should reflect how long it actually takes your customers to decide. Pull conversion path data from GA4 by going to Advertising, then Conversion paths, and looking at the days-to-conversion distribution. If 90 percent of conversions happen within 7 days, a 7-day window captures almost everything with minimal noise. If conversions spread across 30 or more days, a shorter window cuts off real conversions. Do not guess — the data tells you. See Google's documentation on conversion windows for setup details.
Shorter windows are more conservative. A 7-day window counts fewer conversions than a 30-day window, which means lower reported counts, higher CPAs, and lower ROAS. But the conversions you do count are more likely to be genuinely influenced by the ad.
Longer windows are more generous. A 90-day window counts more conversions and gives Smart Bidding more signal. But the additional conversions at the tail end are increasingly likely to be coincidental rather than caused by the ad. The risk: long windows can make unprofitable campaigns look profitable.
Data-driven attribution and fractional conversions
Data-driven attribution (DDA) is now the default in Google Ads. It assigns fractional credit to each touchpoint, so your report may show 14.7 conversions instead of 15. DDA also redistributes credit over time as it processes more data, making historical comparisons slightly noisy.
Google typically recommends at least 300 conversions and 3,000 ad interactions in the past 30 days for DDA to work well. Below that threshold, the model may fall back to last-click without prominently flagging the change. Check Google's attribution model documentation for current requirements.
The reconciliation approach
You cannot make Google Ads, GA4, and the CRM agree. The windows are different, the models are different, and the definitions are different. What you can do is report each system's number alongside the others and explain the expected gap.
A practical reporting structure: use Google Ads conversions for in-platform decisions (bid adjustments, budget allocation, keyword pausing). Use GA4 conversions for cross-channel analysis and overall marketing performance. Use CRM leads for ROI calculations and business accountability.
Show all three. Label each one. The client who understands that 82 Google Ads conversions, 64 GA4 conversions, and 71 CRM leads are three measurements of the same reality — not three conflicting counts of the same thing — is a client who trusts your reporting.
Understanding attribution windows is one piece of interpreting the data that tools like SyncingBeam collect from your analytics sources. When you know which window produced a number, you can explain the gap instead of guessing at it.