Incrementality
Definition
Incrementality measures the causal additional effect of a measure compared to what would have happened without it.
In marketing, ideally a control group is compared with a treated group. This aims to distinguish between mere attribution and actually caused additional effect.
Simply explained
Like not only asking which channel appeared before the purchase, but whether the purchase would have happened anyway without the advertising.
Why it matters in practice
Relevant for advertising budget and campaign evaluation because attribution models do not guarantee causality.
Example from business
A campaign is tested with a suitable control group to estimate incremental conversions instead of just attributed conversions.
Limits and pitfalls
- Output attribution as incrementality; poorly randomized groups; ignoring overlaps and spillover; measuring small effects with insufficient test power.
Origin & history
Incrementality tests are based on controlled experiments and causal inference. Advertising platforms offer, among other things, conversion lift experiments for this purpose.
Use in mid-sized companies
- Possible applications: campaign budget, channel tests, promotions, and other marketing measures with controlled comparison.
Frequently asked questions
Is attribution the same as incrementality?
No. What can randomized experiments with a suitable control group achieve? They can estimate the incremental effect. Other methods require their own assumptions and validation.
Sources
- Conversion Lift · Google Ads Help, Conversion Lift
Sources checked on 10.10.2026.
Editorially reviewed on: