What Are Custom Audiences and How to Build Them Right
When it comes to Facebook (Meta) Ads, Custom Audiences are one of the most powerful tools you can use. They allow you to target people who have already interacted with your business—making your ads smarter, cheaper, and more effective.
In this article, you’ll learn what custom audiences are, how they work, and exactly how to build and use them to create high-converting campaigns.
What Is a Custom Audience?
A Custom Audience is a group of people who already have some kind of relationship with your business. They’ve:
- Visited your website
- Watched your videos
- Engaged with your Instagram or Facebook content
- Given you their email or phone number
- Downloaded your app
- Purchased from you
You use this past behavior to target them with specific ads—usually as part of a retargeting strategy.
Why Custom Audiences Are So Valuable
✅ Warmer than cold traffic
✅ Higher click-through and conversion rates
✅ Lower cost per result (CPC, CPL, CPA)
✅ Essential for building lookalike audiences
✅ Can be segmented by behavior for personalization
Custom Audiences = smart targeting based on real actions.
Types of Custom Audiences (and How to Build Them)
1. Website Visitors
Target anyone who has visited your site.
📌 Setup:
- Requires the Meta Pixel
- Go to Audiences → Create Custom Audience → Website
- Choose time frame (1–180 days) and pages
🔥 Ideas:
- All website visitors (last 30 days)
- People who visited a specific product page
- People who started checkout but didn’t purchase
- Visitors who stayed over 30 seconds
2. Customer File (Email or Phone List)
Upload a list of your leads, customers, or newsletter subscribers.
📌 Setup:
- Go to Audiences → Custom Audience → Customer List
- Upload CSV file with emails, phones, or names
- Match with Facebook profiles
🔥 Ideas:
- People who bought in the last 60 days
- Abandoned email leads
- Event sign-ups
- Webinar registrants
✅ Use this audience to retarget or build lookalikes.
3. Video Engagement
Target people who watched your videos on Facebook or Instagram.
📌 Setup:
- Audiences → Custom Audience → Video
- Choose video(s) and how much was watched:
- 3 seconds
- 15 seconds
- 25%, 50%, 75%, 95%
🔥 Ideas:
- 75%+ viewers = high intent
- Use in middle-of-funnel (MOFU) campaigns
- Great for storytelling or nurturing
4. Lead Form Interactions (Instant Forms)
If you use Meta Lead Ads, you can retarget form activity.
📌 Setup:
- Audiences → Custom Audience → Lead Form
- Choose:
- People who opened but didn’t submit
- People who submitted a form
- People who opened and submitted in last X days
🔥 Ideas:
- Follow up with non-submitters: “Need help finishing your form?”
- Upsell past leads with new offers
5. Engagement on Facebook or Instagram
Target anyone who interacted with your page or profile.
📌 Setup:
- Audiences → Custom Audience → Facebook Page / Instagram Account
- Choose actions:
- Visited profile
- Liked or commented
- Clicked CTA
- Saved a post
🔥 Ideas:
- People who messaged you but didn’t buy
- Engagers from the last 30 days = warmest traffic
- Build trust with testimonial or review ads
6. App Activity or Offline Events
If you have a mobile app or offline sales, you can track users there too.
📌 Setup:
- Requires app integration or offline events API
- Good for advanced setups and CRMs
🔥 Use Cases:
- Retarget app users who didn’t upgrade
- Reach in-store customers with online offers
How to Organize Custom Audiences
Create audience segments by behavior and time frame:
| Audience Name | Type | Duration | Purpose |
|---|---|---|---|
| Viewers_75%_VideoX | Video | 30 days | Retarget with lead magnet |
| Visitors_ProdPage | Website | 14 days | Push to complete purchase |
| FormOpened_NoSubmit | Lead Form | 7 days | Recover abandoned leads |
| Buyers_Last60Days | Customer List | 60 days | Upsell or ask for referral |
| IG_Engagers_30d | 30 days | Nurture or retarget |
✅ Use clear naming so you don’t get lost as your account grows.
How to Use Custom Audiences in Campaigns
- Go to Ads Manager
- At the Ad Set level, choose “Custom Audiences”
- Select one or more lists
- Refine location or device if needed
- Use exclusions to separate campaigns (e.g., exclude buyers from cold ads)
Advanced: Combine Custom Audiences With Lookalikes
Once you have strong Custom Audiences, create Lookalike Audiences to scale.
Examples:
- Lookalike of purchasers = find people similar to your customers
- Lookalike of form submissions = generate leads from similar users
You can create lookalikes from any Custom Audience.
Mistakes to Avoid
❌ Using too small a list (<100 users per country)
❌ Forgetting to update/upload your email list regularly
❌ Not segmenting by action (e.g., lumping all visitors together)
❌ Retargeting forever (keep time frames relevant)
❌ Retargeting without excluding converters = wasted ad spend
Custom Audiences = Your Secret Weapon
With Custom Audiences, you can stop wasting money on broad targeting and start speaking directly to the people who already know you. They’re cheaper to convert, easier to engage, and essential to a smart ad strategy.
The more you know about your audience’s behavior, the better you can speak to them—and custom audiences give you that power.
