What is the `_ga_<container-id>` cookie?it needs consent first

Set by Google Analytics (Google LLC). Expires after 2 years.

Block it until the visitor opts in

Under the ePrivacy Directive (Art. 5(3)) and GDPR, _ga_<container-id> may only be set after the visitor accepts analytics cookies.

Purpose

Holds the GA4 session state for one measurement ID (the part after _ga_): the session number, its start time and whether it engaged.

Every GA4 property sets one of these next to _ga, named after its measurement ID (e.g. _ga_ABC123XYZ).

Cookie details

Cookie name: _ga_<container-id>
Service: Google Analytics
Provider: Google LLC
Category: Analytics
Duration: 2 years
Consent: Required — opt-in

GDPR requirements

Analytics cookies help website owners understand how visitors interact with websites by collecting and reporting information anonymously. Consent is required under GDPR.

For _ga_<container-id> to be compliant, it must be:

Not set on the first visit — not even for a fraction of a second
A consent banner is shown, and the visitor actively accepts analytics cookies
Stays blocked if the visitor rejects or ignores the banner
Listed in your cookie policy with its name, purpose and retention period
Removed or invalidated when the visitor withdraws consent

How to handle it

1
Block it by default
Configure your consent platform (CMP) or tag manager so Google Analytics doesn't load until the visitor accepts analytics cookies.
2
Map it to a consent category
Put it under “Analytics” in your CMP configuration.
3
List it in your cookie policy
Name, purpose, provider (Google LLC) and expiry (2 years).
4
Sign a DPA
Have a Data Processing Agreement with Google LLC covering the data this cookie collects.
5
Verify it works
In a private window, reject cookies and confirm _ga_<container-id> is not set.