Current uses for third-party cookies are largely:
- Remarketing lists and other personalisation techniques
- Measuring marketing effectiveness (view-through conversion tracking)
- Building audiences
- Cross-domain tracking (in some instances)
- Some onsite tools/functionality e.g. live chat, login functionality etc.
The cross-domain tracking aspect allows large companies to build up a comprehensive view of browsing behaviour on a user level, which is one of the key drivers of the change to third-party cookies.
What about first-party cookies?
First-party cookie solutions (such as Google Analytics for website tracking) will continue to function as normal for Chrome.
Some advertising platforms (e.g. Google Ads, Facebook ads, etc.) have options that use a first-party cookie tracking setup that will also be unaffected by the changes to third-party cookies. However, they are still affected by any restrictions applied to first-party cookies (common on many non-Chrome browsers, through blocking plugins, or the use of cookie banners to comply with legal rules, that prevent cookies from being set).
This article is focused on the changes to third-party cookies, however, it is worth keeping in mind that many browsers have also implemented restrictions on first-party cookies (as you can see on the cookiestatus.com website).