Short answer: Google Ads now offers two main attribution models: data driven attribution, the default, which shares credit across the ad clicks that helped a conversion, and last click, which gives all credit to the final click. Data driven usually gives Smart Bidding a better picture of which keywords and campaigns start the journey. Most accounts should keep data driven, and use last click only for a specific reason, such as comparing with an older report.
How each model works
| Model | Credit goes to | Effect |
|---|---|---|
| Data driven | Several ad interactions, based on your account data | Upper funnel keywords and campaigns get some credit |
| Last click | The final ad click before conversion | Brand and bottom funnel keywords look stronger |
Older rule based models such as first click, linear, time decay and position based were removed from Google Ads and GA4.
Example
A customer clicks a generic ad for “running shoes for flat feet”, later clicks a Shopping ad, and finally clicks a brand ad and buys. With last click, the brand ad gets 100% of the credit. With data driven, the generic and Shopping ads also get a share, based on how often similar paths lead to sales in your account.
Why it matters for bidding
Smart Bidding uses your attribution model to value each click. With last click, it may underbid on keywords that start journeys. With data driven, those keywords get credit and can win more traffic. This often helps accounts grow new customer sales.
Where to change it
Open Goals, then Conversions, select a conversion action and edit the attribution model. Changes apply going forward, and they can change how your reports look, so note the date you switched.
Attribution is not the full truth
Every model only sees Google Ads clicks. It does not see what Meta Ads, email or word of mouth did. Use attribution for optimising within Google Ads, and look at total sales, MER and incrementality tests to judge the channel as a whole.
Tips
- Keep data driven on your main conversion actions.
- Compare models in the Attribution reports to see which campaigns gain or lose credit.
- Do not switch models often.
- Report brand and non brand separately.
Frequently asked questions
What is data driven attribution in Google Ads?
Is last click still available?
What happened to first click and linear models?
Does the attribution model affect bidding?
Should a small account use data driven attribution?
Who can review my Google Ads attribution and tracking?
Want to know what really drives your sales?
I can review your attribution and tracking setup. See my Google Ads management and web analytics services, or request a free ads audit. Also read ROAS vs MER vs CAC and Meta Ads attribution settings.