CBO (Campaign Budget Optimization)
Also known as: Campaign Budget Optimization, Advantage Campaign Budget
Campaign budget optimization sets one budget at the campaign level and lets Meta shift spend automatically toward the best-performing ad sets.
What it actually means
With CBO — now labeled Advantage campaign budget — you fund the campaign as a whole instead of fixing a budget per ad set, and Meta continuously reallocates spend to whichever ad set is producing results cheapest right now. This removes the manual chore of shuffling budgets and reacts faster than any human can. The trade-off is control: the algorithm may starve an ad set you care about because another converts marginally cheaper, and small audiences can get crowded out. Minimum and maximum spend limits per ad set restore some balance. CBO rewards clean account structure — fewer, meaningfully different ad sets rather than many overlapping ones.
For a local business running two or three offers at once, CBO acts like a hands-off portfolio manager, quietly pushing budget toward the offer your neighborhood is responding to this week.
Related terms
The learning phase is the period after launching or editing an ad set when Meta's algorithm is still working out who converts, so results are volatile.
The ad auction is the real-time process where Meta decides which ad each person sees, weighing bid, estimated action rate, and ad quality.
An A/B test compares two versions of an ad or page that differ in one element, splitting traffic between them to see which performs better.
ROAS is the revenue generated for every dollar of ad spend, calculated as conversion revenue divided by ad spend.
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