Cost cap
Cost cap is a Meta bid strategy that limits maximum CPA. The platform spends as much as possible while keeping CPA at or below the cap.
What does Cost cap actually mean?
Cost cap is Meta's ‘don't exceed this CPA’ bid strategy. Unlike Target CPA on Google (which averages around the target), cost cap acts as a ceiling: the platform won't bid into auctions where projected CPA exceeds the cap, even if it means underspending the budget.
The trade-off: cost cap protects unit economics at the expense of scale. If the auction gets competitive (Q4 holiday season, new entrants in your audience), cost-cap campaigns can underspend dramatically while target-CPA campaigns absorb the higher costs. For brands where any unprofitable spend is intolerable, cost cap is the safer default.
Cost cap requires at least 50 conversions per week to learn properly. Below that volume the algorithm doesn't have enough signal to model CPA distribution, and campaigns often go into ‘learning limited’ status.
Example
A DTC brand sets a $35 cost cap on a Meta campaign. The campaign won't bid in auctions where Meta's model predicts CPA above $35, even when Daily Budget is unspent. Result: stable economics with variable spend.
When it matters
Cost cap is the right Meta bid strategy when economics matter more than maximum scale. Use it for new product launches and economics-sensitive scaling.
Related terms
Target CPA
Target CPA is a Smart Bidding strategy that aims to maximize conversions while keeping average cost per acquisition at your specified target.
CBO
CBO sets a single budget at the campaign level; Meta auto-distributes across ad sets based on real-time performance.
Advantage+
Advantage+ is Meta's AI-driven campaign suite (Shopping, App and Sales) that automates audience, placement and budget decisions.
CPA
CPA is the cost to drive one conversion event: a purchase, signup, lead or install. It's the universal performance metric.
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