How Long Can a Google Ads Customer Match List Go Without Updates Before It Expires?

A Google Ads Customer Match list has a maximum membership duration of 540 days. Any individual membership that was added or last refreshed more than 540 days ago stops being eligible, and to keep the list usable at all, it needs at least 100 members that have been added or updated within that trailing 540-day window.

Why This Is a List-Freshness Rule, Not a Starting Minimum

It's worth separating this from a different, more commonly cited question — how many matched users a list needs to be used for targeting in the first place. The 540-day rule is about ongoing eligibility over time, not initial creation. A list can clear whatever bar is needed to launch and still lose eligibility months later if it's never refreshed, because individual memberships age out on a rolling 540-day clock from when they were added or last updated, independent of when the list was first created.

What "Refreshed" Actually Means for a Membership

A membership's 540-day clock resets when that specific record is added or updated again — not when the list as a whole is touched. Re-uploading an unchanged file doesn't necessarily refresh every record inside it if the underlying data for a given contact hasn't changed; the mechanism tracks each membership's own add/update timestamp. For a list sourced from a CRM or e-commerce platform, that means an automated, recurring sync job that actually re-submits current customer data is what keeps memberships inside the 540-day window — a one-time upload followed by inactivity will start aging out individual records well before a year and a half passes.

The Practical Floor to Watch

Even with some memberships refreshing on schedule, the list overall needs at least 100 members inside that rolling 540-day window to stay eligible for use. A list that's slowly shrinking — losing more aged-out memberships than it's adding or refreshing — can cross back below that 100-member floor and become ineligible again, even if it successfully cleared it when first launched.

What This Means for List Management

Any Customer Match list built on data that doesn't change often — a one-time trade show attendee list, for instance — needs a deliberate recurring re-upload process even when the underlying contact data itself hasn't changed, purely to keep the membership timestamps current. Lists sourced from continuously updated systems, like an active CRM with ongoing purchase or signup activity, are less exposed to this risk by nature, since new and updated records are added as a byproduct of the business running normally.

Bottom Line

Set a recurring sync — monthly at minimum, more often for smaller lists — that re-submits your Customer Match audience data, rather than treating a single upload as a permanent audience, since Google only counts a membership as current for 540 days from its last add or update.

Sources: Google Ads Help Center, "Fix Customer Match issues with list upload, small list size, or low volume" (support.google.com/google-ads/answer/7474166).