Reach & delivery
What is Bid strategy?
A bid strategy is the rule you give Meta for how to bid in the ad auction on your behalf — whether to chase the most results for your budget, hold to a target cost, or cap each bid. On Meta (Facebook and Instagram) the main options are Highest volume (lowest cost), Cost per result goal (cost cap), Bid cap, and ROAS goal, and the choice shapes how aggressively your ads spend.
Example
Run an ad set on Highest volume and Meta spends the full budget to win as many conversions as it can, letting CPA float. Switch it to a Cost per result goal of $15 and Meta tries to hold your average CPA near $15 — often spending less and delivering fewer conversions, but protecting your margin.
Why it matters
The bid strategy decides the trade-off between volume and cost: Highest volume maximises results but lets CPA drift, while cost or bid caps defend profitability at the price of reach. Picking the wrong one is a common reason a campaign either overspends past break-even or starves and never leaves the learning phase.
How to use and improve it
Start with Highest volume (lowest cost) so Meta has the freedom to exit the learning phase and find your buyers, then add controls only once you have stable data and a clear CPA or ROAS target to defend. When you do set a cost or bid cap, base it on your real break-even CPA — a cap set too tight throttles delivery and blocks learning.
Frequently asked questions
What is the best bid strategy for Facebook ads?
There's no single best one — it depends on your goal and account. Highest volume suits scaling and fresh ad sets that need to learn; cost or bid caps suit mature campaigns defending a known CPA. Test against your own data rather than trusting a blanket rule.
What's the difference between cost cap and bid cap?
A cost cap targets an average cost per result across the ad set, letting individual bids vary to hit that average. A bid cap sets a hard ceiling on each auction bid, giving tighter control but risking under-delivery if the cap is too low.
Why is my ad set not spending its budget?
A cost or bid cap set too low is a frequent cause — Meta can't win enough auctions at that price, so delivery stalls. Loosen the cap or switch to Highest volume to let it spend and learn, then tighten once you have data.
Should I change bid strategy during the learning phase?
Avoid it. Editing the bid strategy resets the learning phase, so the ad set restarts with unstable delivery. Let it stabilise on one strategy first, then adjust deliberately once you have enough conversions to judge.
Related
How does your account score?
A free Meta ads audit gives you a 0–100 score, shows wasted budget, and lists the exact next steps.
Run a free audit