One of the most important metrics within Facebook ads manager is ad frequency.
For those unaware, the ad frequency metric shows you the amount of times each of your advertisements have been seen by a unique user - so an ad frequency of four means that each user who has seen your advert has seen it an average of of times.
This means that you’re able to clearly see how much you’re blanketing the same audience, or how thinly your ad budget is being spread. Conventional wisdom dictates that, on average, the audience needs to see your ad more than once to be able to recall it, and to take action upon it, however, naturally the higher the frequency gets, the less effective your advertising is going to be.
One question I’ve been asked many times is, “what number should I aim for my ad frequency to be?”. There’s no hard and fast rule, however our latest study of over 10,000 ads across multiple accounts shows the following:

This study has taken ad frequency versus average cost per acquisition - and as you can see, there are two general trends here. The peak ad frequency is shown to be between 1.8 and 4 views on average of an ad, and as the frequency rises above that, as does the CPA.
The peak ad frequency is broadly in line with what marketers have been experiencing and advising for a number of years. With attention spans at an all-time low, it's commonplace for consumers to need to see an ad a number of times before they take action.
As the frequency increases, the CPA naturally increases, because if users are continually seeing ads and not taking action, then they're either not the right audience for those ads in the first place, and/or they’re being turned off by the number of times they’re seeing the same ad. If you’ve been shown the same advert 15x or more, you’re likely to get pretty frustrated with that ad, and consequently, the brand serving it to you.
So when it comes to your clients asking you how high their ad frequency should be, you now have a little evidence to tell them not to go beyond a frequency of four, as that’s where your CPA will naturally start to climb. Ideally you want your frequency to be as low as possible while still achieving results, in order to save your ad budget and use it most efficiently.
Expect your frequency to be between 1.8 - 4 for optimum performance when putting your plans together and you won’t be far wrong.