# GA4 Attribution Models and Lookback Windows for Marketers

> GA4 attribution explained: data-driven, paid and organic last click, Google paid channels last click, lookback windows and when each applies.

Source: https://mentionx.ai/learn/ga4/ga4-attribution-models-lookback  
Author: Dipuck Jones, founder of MentionX  
Updated: 4 November 2026  
Level: Practitioner

**GA4 offers three attribution models: data-driven (the default), paid and organic last click, and Google paid channels last click. The model changes how key event credit is split across touchpoints, not how sessions are labelled.** Choose one, document it, and avoid switching mid-quarter.

> **Key takeaways**
>
> - Data-driven attribution uses your property's own converting and non-converting paths.
> - Paid and organic last click gives 100% credit to the last non-direct click.
> - Google paid channels last click credits the last Google Ads click when there is one.
> - Lookback windows: 90 days by default for most key events (30 or 60 optional), 30 days for acquisition events (7 optional).
> - Model changes apply going forward and to all linked Google Ads accounts.

*Checked 4 November 2026 (CET) against Google Analytics Help and Google developer documentation. GA4 menus and limits change, so confirm in your own property. "Our view" marks MentionX opinion. Ledgerline is a fictional company used for illustration.*

## Which model should a marketing team use?

| Situation | Model | Why |
|---|---|---|
| Mixed paid, organic and email, decent volume | Data-driven | Uses your own path data and credits assists |
| Low volume or need for a simple story | Paid and organic last click | Easy to explain and close to what channel reports show |
| Google Ads optimisation focus | Google paid channels last click | Avoids organic taking credit from Ads |

## Where to change it

Go to **Admin → Data display → Attribution settings**. Pick the reporting attribution model and the two lookback windows. Google notes that changes apply going forward, affect all linked Google Ads accounts and can take a few days to show.

## Where you see attributed numbers

- **Advertising → Attribution → Model comparison** (where available) to compare models.
- **Advertising → Attribution paths** to see touchpoint sequences before key events.
- Traffic acquisition reports use session-scoped last-click data, so they won't match model-attributed totals. That is expected.

> **Pro move:** compare data-driven with paid and organic last click for your demo key event once a quarter. Channels that gain under data-driven (often Organic Search, Organic Social or AI Assistant) are assisting; cutting them on last-click numbers is risky.

*Our view:* attribution models answer "how to share credit", not "what caused growth". For AI visibility, pair GA4 with the approach in [connecting AI visibility to pipeline](https://mentionx.ai/learn/measurement/attribution-connecting-ai-visibility-pipeline) and [self-reported attribution](https://mentionx.ai/learn/measurement/self-reported-attribution-adding-chatgpt-forms).

Next: [Consent mode v2: basic vs advanced](https://mentionx.ai/learn/ga4/ga4-consent-mode-v2-basic-advanced). Or return to the [GA4 for Marketers track](https://mentionx.ai/learn/ga4/ga4-for-marketers).

## Common questions

**Which attribution models does GA4 offer?** Data-driven, Paid and organic last click, and Google paid channels last click. The older rule-based models such as linear are no longer offered.

**What is the default lookback window?** 90 days for most key events and 30 days for acquisition key events such as first_visit. You can shorten them in attribution settings.

**Does the attribution model change channel reports?** No. Traffic acquisition reports use last-click session data. The model affects key event credit in the Advertising section and in Google Ads.

## Sources

- Google Analytics Help, [Get started with attribution](https://support.google.com/analytics/answer/10596866)
- Google Analytics Help, [Select attribution settings](https://support.google.com/analytics/answer/10597962)
- All accessed 4 Nov 2026.

## Frequently asked questions

### Which attribution models does GA4 offer?

Data-driven, Paid and organic last click, and Google paid channels last click. The older rule-based models such as linear are no longer offered.

### What is the default lookback window?

90 days for most key events and 30 days for acquisition key events such as first_visit. You can shorten them in attribution settings.

### Does the attribution model change channel reports?

No. Traffic acquisition reports use last-click session data. The model affects key event credit in the Advertising section and in Google Ads.

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Written and reviewed by Dipuck Jones for MentionX Learn. The HTML version of this page: https://mentionx.ai/learn/ga4/ga4-attribution-models-lookback