Attribution model
data-driven attribution / last click attribution / GA4 attribution models
An attribution model is the rule or algorithm that decides which clicks and visits get credit for a sale or lead. Google Ads defaults most conversions to data-driven attribution, and GA4 offers three models, so the same lead can be credited differently depending on the report.
Google's help pages define an attribution model as a rule, a set of rules, or a data-driven algorithm that decides how credit is assigned to the touchpoints on a customer's path. Last click gives all the credit to the last-clicked ad and its keyword. Data-driven attribution spreads credit based on the account's own past data for that conversion.
Google Ads makes data-driven the default for most conversion actions. GA4's Attribution reports offer three models: data-driven, paid and organic last click, and Google paid channels last click. GA4's data-driven model uses machine learning on both converting and non-converting paths.
Two details make numbers move. GA4's models give direct visits no credit unless the whole path to the key event was direct. And GA4 says conversions can be reattributed for up to 7 days after they happen, so last week's figures can change after they were first reported.
Creditable channels differ too. In Google Ads a conversion can be set to credit only Google paid channels, all paid channels, or paid and organic channels. The same lead can therefore show up with different credit in each tool.
In practice
A roofing lead first finds the company through an organic search, later clicks a Google ad, and calls a day after that. In a report crediting only Google paid channels, the ad gets all of it. In GA4's paid and organic last click model, the last non-direct click, the ad, gets the credit. In a data-driven model, the organic visit and the ad can share it, depending on what the account's data shows.
Not the same as
- Conversion window
- A conversion window sets how long after a click a conversion can still be counted. The attribution model decides how credit for that conversion is shared among the clicks inside the window.
Why it matters to you
When two reports disagree about what produced a lead, the attribution model and the creditable channels are usually the first things to compare. Decisions about cutting a channel should rest on the same model across the period being compared.
What to ask or check
- 01Which attribution model and creditable channels does each report use?
- 02Did the model change during the period being compared?
- 03Are recent conversion figures final, given GA4 can reattribute them for up to 7 days?
What people get wrong
That Google Ads and Google Analytics should report the same credit for a lead. They can use different models and different creditable channels, and GA4's models give no credit to direct visits unless the whole path was direct.