What is last-click attribution?

Last-click attribution is a marketing measurement model that gives 100% of the conversion credit to the last eligible marketing interaction before a customer completes a desired action. That action could be a purchase, form submission, sign-up, or another tracked conversion.

It helps marketers identify the final recorded touchpoint associated with a conversion, but it does not give credit to earlier interactions that may have influenced the customer’s decision.

How does last-click attribution work?

Suppose a customer buys a diamond ring from a Shopify store after interacting with the brand through several channels:

1. Instagram ad: The customer discovers the jewellery brand.

2. Google search: The customer searches for the brand and visits its website.

3. Email campaign: The customer clicks an email featuring the ring.

4. Google Ads retargeting: The customer clicks a retargeting ad and completes the purchase.

Under a last-click model, the final eligible interaction—in this example, the retargeting ad—receives all the conversion credit, according to the model’s tracking and eligibility rules.

Key features of last-click attribution

• Simple measurement: Easy to understand and interpret.

• Focuses on the final interaction: Identifies the last eligible touchpoint before conversion.

• Useful for performance reporting: Helps evaluate channels that directly precede conversions.

• May undervalue earlier channels: Awareness campaigns and other early interactions receive no credit under this model.

• Depends on tracking: Missing data, consent settings, and attribution rules can affect which interaction is counted.

Last-click vs. multi-touch attribution

When is last-click attribution useful?

It can be useful for simple reporting, understanding the final recorded interaction, or comparing results with historical reports that use the same model. However, it should not be the only measure used to evaluate channels that build awareness or influence customers earlier in their journey.

In short: Last-click attribution assigns all conversion credit to the last eligible marketing interaction before a conversion, making reporting straightforward but potentially overlooking the influence of earlier touchpoints.