Custom audience

A custom audience is a Meta ad audience made up of people who already have some connection with your business. Unlike interest-based targeting, which relies on what Meta infers about people, custom audiences are built from your own data or from interactions with your content on Meta.

Sources for custom audiences

• Website: visitors or people who triggered specific events, collected via the Meta Pixel and Conversions API.
• Customer list: emails or phone numbers you upload, which are hashed before matching.
• App activity: actions taken in your app.
• Engagement: people who watched your videos, interacted with your Instagram account or Facebook Page, or opened a lead form.
• Catalog: people who interacted with products in your catalog.
• Offline activity: events from physical stores or other offline channels.

How they are used

• Retargeting: showing ads to people who visited or engaged but did not buy.
• Exclusions: keeping existing customers out of prospecting campaigns, or recent buyers out of discount campaigns.
• Sources for lookalike audiences: using your best customers as a seed.
• Signals for automation: some Advantage+ settings use custom audiences as suggestions or to define existing customers.

Good practice

• Make sure you have a lawful basis and appropriate consent for any customer data you upload, especially under the GDPR in the EU and the UK GDPR.
• Keep audiences fresh by using rolling time windows, such as visitors in the last 30 days.
• Name audiences clearly so you can tell them apart in Ads Manager.