What is the ARRAffinity cookie?
When using Microsoft Azure as a hosting platform and enabling load balancing, this cookie ensures that requests from one visitor's browsing session are always handled by the same server in the cluster.
Our October 2026 scan found it on 10 sites (0% of the 2,450 we scanned), set before any consent.
- Purpose
- Functional
- Belongs to
- Azure / Microsoft
- Set as
- First-party (under the site's own domain)
- Typical lifetime
- Session (vendor says: 1 year)
Sites that set ARRAffinity before consent
The highest-ranked 10 of 10 sites.
- lecturas.com5 tracking companies
- aboutcookies.org2 tracking companies
- screenconnect.com7 tracking companies
- powerbi.com1 tracking company
- cancer.org1 tracking company
- dataprivacyframework.gov2 tracking companies
- serverdata.net3 tracking companies
- dmca.com2 tracking companies
- redcross.org16 tracking companies
- ct.gov5 tracking companies
Related cookies
Other cookies from Azure / Microsoft.
- MUID38 sites
- ASP.NET_SessionId23 sites
- _uetsid22 sites
- _uetvid21 sites
- MR16 sites
How to stop it
Declining non-essential cookies in a site's consent banner should stop ARRAffinity being set on later visits. Blocking third-party cookies in your browser settings stops the third-party kind everywhere, and clearing cookies for a site removes any it already set.
Description from the Open Cookie Database (Apache 2.0).
Understanding this page
- How cookie lifetimes work, and why a 13-month _ga matters
What a cookie's "expires" field actually controls, why Google Analytics ships a 2-year default that many sites cut down to 13 months, and how Safari's 7-day cap on script-set cookies changes the picture.
- First-party vs third-party cookies (and why "first-party" still tracks you)
What the distinction actually means technically, why browsers only block one of the two, and how CNAME cloaking, server-side tagging and cookies like _ga let sites keep tracking under their own domain.
- How to block or limit trackers
Browser privacy settings, content blockers, Global Privacy Control and clearing cookies compared honestly — what each one actually stops, what it doesn't, and what it costs you in return.