Glossary: Third Party Cookie

A third party cookie is set by a domain other than the website a visitor is currently on (typically by an ad network or embedded tool) and is often used to track users across multiple sites. Major browsers have been phasing out third party cookie support due to privacy concerns.

Examples

• An ad network sets a third party cookie to track a user’s browsing across multiple sites for retargeting.

• A browser blocks a third party cookie from an embedded widget by default.

• A company shifts to first party or cookieless tracking as third party cookie support declines.

Related reading

Explore Cookie, First Party Cookie, Cookieless Analytics, and PII (Personally Identifiable Information).

FAQs

Why are third party cookies being phased out?

Growing privacy concerns and regulation have led major browsers to restrict or block them by default.

What can teams use when third-party cookies are unavailable?

Options include first-party measurement, consented account data, server-side events, and aggregate reporting. Each has different coverage and privacy implications; no identifier is a universal substitute.

Do third-party cookies affect crypto app analytics?

They can affect the website portion of an analytics setup. Public blockchain records are collected independently of browser cookies, but connecting those records to site activity requires a separate, documented signal.