Glossary
Customer Match
Customer Match is a Google Ads audience feature that allows advertisers to upload hashed lists of first-party customer data — email addresses, phone numbers, mailing addresses, and mobile device IDs — to target or exclude those customers across Google's advertising properties including Search, Shopping, Display, YouTube, and Gmail. Advertisers can use Customer Match to create audiences for retargeting existing customers with upsell or loyalty offers, to build Similar Audiences that prospect for new users resembling their best customers, or to suppress current customers from seeing acquisition ads. Data is hashed using SHA-256 before upload, and Google matches the hashed identifiers against its own user database without revealing individual identities. Customer Match requires compliance with Google's customer data policies, including adequate notice and consent from users. As third-party cookies are deprecated across browsers, Customer Match becomes one of the most durable identity signals in paid media — it relies on first-party data that the advertiser owns directly, making it resilient to browser privacy changes.