New changes have come to Facebook advertising. This is maybe the biggest change after the introduction of lookalike and custom audiences.
Campaign budget optimization (CBO) makes the most efficient use of your budget spending to get you the overall best results, and ensure that the cost of those results align with your bid strategy.
A campaign budget is a budget you set at the campaign level (rather than the ad set level). The amount you set can apply to each day the campaign runs (daily budget) or over the lifetime of the campaign (lifetime budget). All campaign budgets use campaign budget optimization.
How it works
CBO uses your campaign budget and your bid strategy – which might be, for example, lowest cost per action (CPA) or highest return on ad spend (ROAS) – to automatically and continuously find the best active opportunities for results across your ad sets. Then we distribute your campaign budget in real time to get those results.
You can create ad sets that have different start and end dates or times, as CBO considers each active ad set’s schedule (ads can run all the time or on a schedule). However, remember that CBO may not spend your budget equally for each ad set since we optimize for your overall campaign budget. For example, if you have 2 active ad sets in one campaign, we might spend 90% of your budget on the first ad set if that’s how we can get your campaign the overall lowest CPA or highest ROAS (as compared to the other ad set).
To avoid inefficient spending, it’s important to not manually pause and unpause your ad sets to mimic automatic ad set scheduling. CBO reserves and spends your campaign budget on active ad sets. Manually mimicking ad set schedules can cause CBO to spend your budget primarily on only one ad set.
For example, if your campaign budget spend is for 2 ad sets, one active and one scheduled to run in the future, pausing the future ad set would cause our system to focus on spending the budget entirely on the active ad set. (It would no longer register an additional ad set to consider.) By the time you unpause the scheduled ad set and it starts to run, there might not be any budget left in the campaign.