Build a Customer List Audience from a CSV or Smart List

A customer list audience lets Meta match the emails or phone numbers you already hold against its own users, so you can show ads to existing customers or use them as the source for a lookalike. You can feed it from a CSV file or directly from a Smart List of Contacts.

Start the audience

1. Open the ad set's Audience Controls > Intended Audience > Retargeting dropdown and choose Create a Custom Audience, or go to Marketing > Ad Manager > Settings > Audiences > Create new audience.
2. Choose Customer List as the source and continue.
3. Accept Meta's customer list terms if prompted. This is required before an audience can be created.

Option 1: Upload a CSV

Upload a file of customer identifiers, such as emails or phone numbers. Use the sample file provided as your template. If headers or values do not follow Meta's formatting rules, the upload fails with an error, so fix the file and try again.

Option 2: Use a Smart List

1. Choose Use Smart List.
2. Select one or more Smart Lists. Only lists already created in Contacts appear.
3. Under Advanced Conditions, decide how the audience behaves:
   • Static: answer "No, only include the contacts currently on the Smart List". The audience is frozen at today's members.
   • Dynamic: answer "Yes, include the dynamic updates". Contacts joining or leaving the Smart List are added or removed automatically.
4. Check the contact count shown.
5. Add a name and optional description, then click Create Audience. The summary confirms whether it is static or dynamic.

After creation

The audience appears in the Retargeting dropdown and on the Audiences tab. It must reach Ready status, and Meta enforces a minimum audience size before it can be used.

Good to know: Choose dynamic for lists like "Past customers" that keep growing, and static when you want a one-time snapshot to compare results fairly.