What is the personalization_id cookie?
Stores a unique ID used by X (Twitter) for integration and ad personalisation when embeds or the conversion tag are present.
Marketing Needs consent
| Cookie name | personalization_id |
|---|---|
| Set by | X (Twitter) |
| Category | Marketing |
| Typical duration | 2 years |
| Domain | .twitter.com / .x.com |
| Consent required? | Yes — before it is set |
Does personalization_id need consent?
Yes. personalization_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 personalization_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 personalization_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 personalization_id
- See it: open your browser's developer tools → Application (Chrome/Edge) or Storage (Firefox) → Cookies, and look for
personalization_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 personalization_id from being set at all.
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.
Fixing pre-consent cookies
If a scan shows personalization_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 personalization_id differently. This is general information, not legal advice.