Meta Business Help Centre
Create a customer list custom audience


Note: Targeting options are limited for audiences that include people under the age of 18 in most countries, under 20 in Thailand and under 21 in Indonesia. Learn more about targeting options to reach teens and how this update may affect your ad sets.
Before you begin
- Ensure that you can create this type of audience. You can only create a customer list custom audience if you're the owner of the ad account connected to Meta Business Manager or the owner has provided you with either admin or advertiser permissions. Note: If your account is new or if you've recently linked to an existing account, it may take a few weeks before you're able to create or share a customer list custom audience. If your new account is part of a tenured business portfolio, you may be able to go through business verification.
- Prepare your customer list in advance. To make a custom audience from a customer list, you provide us with information about your existing customers and we match this information with Meta profiles. The information on a customer list is known as an "identifier" (such as email address, phone number, address) and we use it to help you find the audiences that you want your ads to reach. Your customer list can either be a CSV or TXT file that includes these identifiers. To get the best match rates, use as many identifiers as possible while following our formatting guidelines. You can hover over the identifiers to display the formatting rules and the correct column header. For example, first name would appear as fn as a column header in your list. Alternatively, we have a file template that you can download to help our system map to your identifiers more easily. (You can upload from Mailchimp as well).
Create a customer list custom audience
- Add your customer list: You can create your custom audience in Meta Ads Manager. Once in your account, go directly to Audiences, then go to Create audience > Custom audience > Customer list.
- Prepare your customer list: Select the identifiers to include, then add the customer list that you want to use for your new custom audience and give it a name.
- Review your customer list: Confirm that you mapped your identifiers correctly or check to see that all errors are resolved. You'll get one of the following notifications:
- The green tick symbol
means that your identifiers were mapped correctly and are ready to be hashed, then used for the matching process.
- The yellow exclamation symbol
means either that you chose not to include certain identifiers or that some identifiers need to be manually updated. You have higher chances of getting a better match rate to build your audience if you make the corrections before uploading your file.
- Upload your customer list: Once your list has been added and is ready for use, select Upload and create.
When we've finished hashing your customer list information, we'll let you know that your audience is ready to use. Once ready, you can immediately create an ad to reach your new custom audience, or create a lookalike audience to find new people who share similar behaviours and interests with your existing customers.
Note: Before we use your uploaded list for the matching process, the information in your customer list is hashed and will be unidentifiable at an individual level. Hashing is a type of cryptographic security method that turns your identifiers into randomised code and cannot be reversed. (Depending on the size of your list, this may take a few minutes).