Skip to content
CookieTosser

What is the cto_bundle cookie?

Set by Criteo to store the identifiers and ad-serving data it uses to show retargeted ads based on the products or pages a visitor has viewed on sites that use Criteo.

Our October 2026 scan found it on 58 sites (2% of the 2,450 we scanned), set before any consent.

Purpose
Advertising
Belongs to
Criteo
Set as
First-party on 2% of sites, third-party on 98%
Typical lifetime
13 months (vendor says: About 13 months, per Criteo's cookie policy.) — about what the vendor documents

Sites that set cto_bundle before consent

The highest-ranked 30 of 58 sites.

Show 20 more sites

How to stop it

Declining non-essential cookies in a site's consent banner should stop cto_bundle 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 written by CookieTosser, for a cookie the Open Cookie Database doesn't cover.

Understanding this page