The Facebook best practice for campaign structure is to minimize the number of campaigns in the account. This can be accomplished by the creation of campaigns tied to geography and type of bidding. For example, common campaigns will target the United States with a bidding objective of App Event Optimization (AEO), such as a purchase or registration, or use Value Optimization Bidding to target high-value payers versus those only willing to pay $0.99.
Once you have minimized the number of campaigns being used, you will create ad sets that target specific audiences that do not overlap with other ad sets. Following this structure will allow you to efficiently put up to 20 ads per ad set, drive minimum auction competition and efficiently enable one of Facebook’s most compelling new newest features, Campaign Budget Optimization (CBO).
Until CBO became available, advertisers were required to have to spend hours manipulating budgets to make sure the budget was spent on the best performing ad sets. With the launch of CBO, Facebook automatically re-allocates budget without human intervention to the most efficient ad set.
An important byproduct of this innovation is its impact on the broader Facebook ad tech ecosystem. In our opinion, Facebook has rendered unnecessary the external third party SaaS and self-service platforms that are based on proprietary rules or “black box “artificial intelligence. To put it simply, Facebook’s native tools are now more efficient at bidding and budgeting than third-party solutions, and they are free. Having said that, they could improve capabilities with ad building and reporting, and neither Facebook or Google’s native tools offer solutions that span across social ad networks (i.e. Facebook, Instagram, Google App Campaign, Snap, Pinterest, etc).
By keeping within the best practice structure of the account, campaign, ad set an ad, Facebook will run your ads in a “learning phase,” which can graduate to the “optimized phase” for more efficient results. Typically it takes 50 conversions per ad set per week to graduate from learning into optimized.
It’s important that you do not have multiple ad sets with the same campaign objective and bid type with overlapping audiences; however, it’s unclear if there’s an ideal volume of ad sets per campaign and how budget influences the decision. A higher volume of ad sets will divide the CBO campaign budget by more ad sets and usually will cause a lower average spend per ad set. By increasing the volume of ad sets, you may be able to lower the cost per acquisition (CPA) and return on advertising spend (ROAS), unless Facebook biases an individual set ad, which it does from time-to-time.
As we understand the current algorithm, significant edits to budgets occur with changes over 40% and to bids with changes greater than 30%. Modifications beyond these thresholds will force ad sets out of the optimized phase and back into the learning phase, and will result in increased CMPs and less efficient spend.
The maximum number of ads per ad set is 20. Each ad should have a unique creative combination of image, video, ad copy, call to action. Determining the ideal volume of ads per ad set and how your daily or lifetime budget influences the decision is still being tested. However, we do know that a higher volume of ads allows Facebook to rotate more creative and identify potential winners across an audience, and it also reduces creative fatigue. Facebook now offers asset customization so you can specify creative formats to a given placement, and this will further help Facebook optimize with the right ad to the right audience and placement.
How often should you add new creative to existing ad sets? Do you risk significant edits for top ad sets by introducing new ads? Today the API does not have variables to help you understand ad fatigue. We recommend you look at first-time impression ratio, cumulative reach, CTR and audience reach as proxies for fatigue.