Customer Match Minimum List Size

Customer Match lets you upload your own customer list (like an email list) to target or exclude with ads. Google requires a minimum of 100 user records per uploaded list, and recommends at least that many to make sure ads actually serve against it. Because not every uploaded contact matches to a real account, a list needs to be comfortably above that minimum to clear the threshold in practice — a plain count of 100 rows isn't a guarantee of 100 usable matches.

For a small business with a modest customer list, this is a real gate: a list that looks reasonably sized on paper can still fall short once match rates are accounted for. Lists also need to stay active — Google expects at least 100 members to remain within a list's ~540-day membership window, so an old, unrefreshed list can quietly drop below the usable threshold over time.

Is my customer list even big enough to use for ad targeting?

Ask datanephew to check your uploaded audience list's size. Aim comfortably above 100 records, since only a portion will actually match to real accounts.

My customer list used to work for targeting and now it doesn't seem to — why?

Ask datanephew to check the list's current size and how recently it's been updated. An older list that hasn't been refreshed can drop below the usable minimum over time.