Definition
Campaign budget optimisation sets the budget at campaign level and lets Meta distribute it across ad sets. Meta now calls it Advantage campaign budget.
Campaign budget optimisation explained
CBO moves spend toward the ad sets producing the best results in real time. It works well for scaling but can starve new ad sets of budget during tests.
Example
A campaign with a 300 dollar daily budget automatically spends most of it on the best performing of three ad sets.
See it in real ads
Browse millions of real Facebook and Instagram ads to see how top advertisers put these ideas into practice.