What are third-party cookies?

Third-party cookies are set by a domain other than the one you are visiting, usually by embedded services like ad networks, analytics tools, chat widgets, and social media pixels. They are the primary target of cookie consent rules because they enable cross-site tracking.

Where they come from

Any external script your pages load can set cookies under its own domain: advertising tags, video embeds, font services, A/B testing tools, and social buttons. The site owner often did not choose these directly; they arrive bundled with a plugin or embed.

Why browsers are phasing them out

Safari and Firefox block most third-party cookies by default, and Chrome has tightened its handling. Consent rules go further in Europe: even where the browser allows them, setting them without consent is not lawful.