ScanCookies

← Cookie dictionary

What is the guest_id cookie?

Identifies a browser to X (Twitter) for embedded timelines, share buttons and abuse prevention.

Marketing Needs consent

Does guest_id need consent?

Yes. guest_id is a marketing cookie, and under the EU ePrivacy rules (and the Irish ePrivacy Regulations) a site must get your prior, informed consent before setting it. If you see guest_id on a site before you click "Accept" on a cookie banner — or on a site with no banner at all — that is very likely a compliance problem.

Is guest_id a tracking cookie?

Builds a profile to target advertising, usually across sites. Always requires prior consent.

In practice that means X (Twitter) can recognise your browser across different websites to build an advertising profile. It is not malware and it cannot read files on your device — but it is exactly the kind of cookie consent law is designed to cover.

How to see and remove guest_id

  • See it: open your browser's developer tools → Application (Chrome/Edge) or Storage (Firefox) → Cookies, and look for guest_id.
  • Remove it: clear cookies for the site, or use your browser's "Clear browsing data" for cookies. It will reappear if you keep using the site and consent is in place.
  • Stop it being set: decline non-essential cookies on the site's banner. On a compliant site, clicking "Reject all" prevents guest_id from being set at all.
Run it the other way round

Want to know which cookies your site sets — and whether any fire before consent? Scan it free and get the full list, categorised, with the ones that load too early flagged.

Scan your website →

Fixing pre-consent cookies

If a scan shows guest_id or other tracking cookies loading before the visitor consents, the fix is a consent management platform (CMP) that blocks non-essential tags until the visitor agrees. Cookies.ie is our GDPR / ePrivacy CMP — EU-hosted, with a real one-click "Reject all" and consent logging. See the fix guide for pre-consent trackers.

Related cookies

Cookie purposes and durations reflect vendor documentation and common consent databases as of 2026-06-25; a specific site may configure guest_id differently. This is general information, not legal advice.