What is the _uetsid cookie?
Microsoft Advertising Universal Event Tracking session cookie, used to track conversions from Bing ads.
Marketing Needs consent
| Cookie name | _uetsid |
|---|---|
| Set by | Microsoft Advertising (UET) |
| Category | Marketing |
| Typical duration | 1 day |
| Domain | first-party |
| Consent required? | Yes — before it is set |
Does _uetsid need consent?
Yes. _uetsid 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 _uetsid 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 _uetsid a tracking cookie?
Builds a profile to target advertising, usually across sites. Always requires prior consent.
In practice that means Microsoft Advertising (UET) 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 _uetsid
- See it: open your browser's developer tools → Application (Chrome/Edge) or Storage (Firefox) → Cookies, and look for
_uetsid. - 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 _uetsid 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 _uetsid 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
_uetvid— Microsoft Advertising (UET)_gcl_au— Google Ads (Conversion Linker)NID— GoogleIDE— Google DoubleClick
Cookie purposes and durations reflect vendor documentation and common consent databases as of 2026-06-25; a specific site may configure _uetsid differently. This is general information, not legal advice.