Customer Match | Connecting CRM Lists to Ads

Customer Match lets you upload your customer list to Google in hashed form and use it on the advertising side. Even if those people never visited your site, you can reach them through their email or phone number.

Three uses

First, exclusion. Removing existing customers from new-customer campaigns saves money directly in most accounts. It is the easiest and fastest-returning use.

Second, repeat sales. Showing ads to customers who bought a particular product when a complementary item or renewal period arrives is the cheapest source of sales — they already know you.

Third, as a signal. An uploaded list tells automated campaigns such as Performance Max what a good customer looks like, speeding up the algorithm’s search for similar people.

Data quality determines match rate

Not every record in an uploaded list matches. If the email a person uses on their Google account differs from the one you hold, no match is made.

The way to raise the rate is sending more fields: email, phone, name and address together improve matching. List hygiene matters too — old, incorrect and duplicated records lower the rate.

Hashing and privacy

Data is hashed one-way before upload; Google never receives plain email addresses. It is still data sharing and has to be handled under privacy law.

Your privacy policy has to describe marketing-purpose data sharing, and customers must be able to object. Not including people who did not consent matters equally. I handle that side together with Consent Mode setup.

Minimum list size

Google requires a minimum number of matched users before a list can serve. Small lists never pass that threshold and cannot be used in campaigns.

In that case using the list whole rather than splitting it, or using it only for exclusion, is more practical.

How do we start? First I look at the structure of your customer data and its consent status. I send the upload plan and how it should be used in each campaign, in writing. You can reach me from the contact page.

Frequently Asked Questions

How often should I update the list?

As new customers are added. An out-of-date exclusion list keeps advertising to new customers and defeats the purpose.

Can I use a competitor’s customer list?

No. You can only upload data you collected with consent. Purchased lists are both a policy violation and a legal risk.

My match rate is low. What should I do?

Send more fields and clean the list. Also accept it will never be complete; people do not always use their shopping email on their Google account.