GA4 default attribution model change
Google announced that, starting in 2023, Google Analytics 4 would deprecate several rule-based attribution models — first-click, linear, time-decay, and position-based — in the Attribution settings and reports. After the change, GA4 offers data-driven attribution (the default for new properties) and a paid-and-organic last-click model. Knowing exactly which models survived prevents teams from chasing reports that no longer exist.
What changed
Google Analytics 4 originally exposed several attribution models in its Attribution settings and Model comparison report. Google documented that, over 2023, it would remove the first-click, linear, time-decay, and position-based models from GA4. Only data-driven attribution and a paid-and-organic last-click model remained selectable for cross-channel conversion credit.
Data-driven attribution became the default model for GA4 properties, replacing the simpler rule-based options that earlier analytics products had popularised.
Why it matters for reporting
Removing models is not a bug to troubleshoot — it is a deliberate narrowing of the menu. Teams that built dashboards or comparisons around, say, linear attribution had to migrate to data-driven or last-click.
Because different models distribute credit differently, switching can change which channels look effective. When comparing historical figures across the change, note which model produced each number rather than assuming a like-for-like trend.
- Removed: first-click, linear, time-decay, position-based
- Retained: data-driven (default) and paid-and-organic last-click
- Model switches can shift channel credit, not just totals
How it appears in analytics and logs
If an old GA4 model is missing, it was deprecated — not broken. Conversion credit now reflects data-driven or last-click logic, which can shift historical comparisons.
Diagnostic use case
Explain to stakeholders why first-click or linear attribution reports vanished from GA4, and which models remain available for cross-channel conversion credit.
What WebmasterID can help detect
WebmasterID reports observed first-party events independent of any single platform's model, giving you a stable baseline when a vendor changes which attribution models it offers.
Common mistakes
- Treating a missing GA4 model as a tracking failure.
- Comparing pre- and post-change numbers as if the model were constant.
- Assuming data-driven and last-click credit channels identically.
Privacy and accuracy notes
This is an educational summary of a documented product change, not legal or compliance advice; verify current GA4 behavior against Google's own Help Center.
Related pages
- Data-driven attribution: promise and caveats
Data-driven attribution (DDA) assigns credit using a model trained on a site's own conversion paths rather than a fixed rule like last-click. Done well it credits assist touches more fairly. Its caveats are real: it needs enough conversion volume, it is a model not a measurement, and it cannot see touches that were never tracked.
- Attribution in GA4
Google Analytics 4 (GA4) implements attribution with a data-driven model as the default for its conversion reporting, plus rules-based options, configurable lookback windows, and default channel groupings. It also distinguishes attribution used in GA4 reports from the conversions Google Ads counts. This page describes GA4's attribution posture and the settings that change how credit appears.
- GA4 paid and organic last-click model
Alongside data-driven attribution, Google Analytics 4 retains last-click models that assign 100% of conversion credit to the final touch. GA4 documents a paid-and-organic last-click model that credits the last channel and, like last-non-direct logic, avoids crediting a direct visit when a prior campaign click is available. Understanding this default-eligible model clarifies how GA4 reports single-touch credit after the 2023 model changes.
- Compare with Google Analytics
How WebmasterID differs from GA4's attribution model menu.
Sources and verification notes
- Google Analytics Help — Attribution and attribution modelingDocuments the GA4 attribution models available after the deprecation of rule-based models.
Last reviewed 2026-06-24. Facts are checked against primary/official sources where available; uncertain specifics are marked “Data not yet verified” rather than guessed.