Most teams seed lookalikes once and forget about them. The seed list ages, includes churned customers, and gradually drifts away from your current ICP. Cometly keeps the seeds live by pushing your customer list (with appropriate filters) to each platform on a weekly cadence.
Which seeds to sync
Sync at least three audiences: paying customers (the inclusion seed), churned and free-only users (the exclusion seed), and engaged accounts that haven’t yet converted (the retargeting seed for ABM).
For SLG: also sync 'closed-won pipeline by deal value' as a value-based custom audience — which lets the platforms run value-weighted bidding on lookalikes.
For PLG: sync 'paying customers by plan' so you can build separate lookalikes for high-LTV plans (Pro Annual, Enterprise) versus low-LTV plans.
- Paying customers (inclusion seed) — refreshed weekly
- Churned/free users (exclusion seed) — refreshed weekly
- Engaged accounts (retargeting seed for ABM) — refreshed daily
- By-plan or by-deal-value seeds for value-based bidding
Lookalike sizing
1% lookalikes are tight matches, best for high-intent retargeting and remarketing. 5–10% lookalikes are looser, best for prospecting at scale. Run both concurrently as separate ad sets and compare performance — most teams find the right mix is somewhere in the middle.
Refresh seeds at least monthly. A six-month-old seed reflects last quarter’s ICP, not this quarter’s, and lookalikes built from it will trend toward your old customer base.
What to watch for.
- Seeding lookalikes from the wrong list
All-customer lookalikes include churned and low-LTV users. Filter to active high-LTV plans or active pipeline.
- Forgetting exclusion audiences
Without exclusions, you’ll keep paying for impressions to existing customers and free-tier users. Sync exclusions as aggressively as inclusions.
- Letting seeds go stale
Six-month-old seeds drift. Refresh weekly for paying customers, daily for engaged-account audiences.
Recap.
- Sync 'paying customers' as a high-intent lookalike seed (refresh weekly)
- Sync 'churned customers' and 'free-only users' as exclusion audiences
- Sync 'engaged accounts' for ABM retargeting — including non-form-fill engagers
- Use 1% lookalikes for tight match, 5–10% for prospecting
- Refresh seeds at least monthly so the audience reflects your current ICP, not last quarter’s