What is First-party data?
First-party data is information collected directly by you from your own audience on your own site or product, as opposed to obtained from a third party or gathered across other sites. It is more reliable and more durable than third-party data, but the label describes who collected it — not whether it is personal, or whether consent was required.
The parties
- First-party — you collected it, from your own audience, on your own property.
- Second-party — someone else’s first-party data, shared with you deliberately.
- Third-party — collected across many sites by a company with no direct relationship to the person.
- Zero-party — volunteered outright: a preference chosen, a survey answered.
Third-party data is the category browsers and regulators have spent a decade dismantling. First-party has become the default plan because it survives that.
The mistake in the label
“First-party” is frequently used as a synonym for compliant. It is not. It says who collected the data, and nothing about what the data is.
A first-party cookie holding a durable identifier is still device storage, so it still needs consent under ePrivacy. A first-party database of behavioural profiles is still personal data under the GDPR. Moving collection onto your own domain changes the technical path, not the legal category.
First-party analytics
Applied to analytics, the term usually means the measurement runs on infrastructure you control or pay for directly, rather than being handed to a network that also monetises it elsewhere.
Concretely that means: the data is not joined with an advertising graph, not used to target your visitors on other sites, and not resold. That is a genuine and meaningful difference from ad-funded analytics — and it is compatible with collecting no personal data at all, which is the stronger version of the same idea.