Upload Customer Lists CRM Lists to Meta Ads

A Customer List Custom Audience lets you upload a list of contacts — typically email addresses, phone numbers, or names — from your CRM or email marketing tool. Meta hashes and matches those identifiers against its user database so you can show ads specifically to people already in your customer or prospect list on Facebook and Instagram.

Meta accepts several identifiers including email addresses, phone numbers, first and last names, city, country, date of birth, gender, and mobile advertiser IDs. The more identifiers you include per contact, the higher your match rate will be. Email addresses are the most commonly used and typically yield the best match rates.

Meta requires a minimum matched audience size of 100 people for the audience to be usable in a campaign. In practice, you should aim for at least a few hundred matched contacts for meaningful targeting. Match rates typically range from 40% to 70% depending on the quality and freshness of your data, so upload more contacts than the minimum to ensure you clear the threshold.

Meta hashes all personally identifiable information (PII) before it is sent to their servers, meaning your raw contact data is never stored by Meta. The hashing is done locally in your browser before transmission. You should still ensure you have the appropriate legal basis (e.g., consent) to use your contacts' data for advertising purposes in accordance with GDPR, CCPA, and other applicable privacy laws.

Yes — this is one of the most powerful uses of a Customer List. Once your Custom Audience is created and has enough matched users, you can click Create Lookalike Audience from the Audiences dashboard. Meta will find new users on Facebook and Instagram who share similar characteristics to your existing customers, letting you expand your reach to high-quality cold audiences.

If you select Yes to Customer Value, Meta will prompt you to include a monetary value column in your upload (e.g., lifetime revenue per customer). This enables you to create a Value-Based Lookalike Audience, where Meta prioritises finding users who resemble your highest-value customers rather than just any customer. Select No if your list is a simple email export without revenue data.