As with many beauty questions, it depends, and there is no one-size-fits-all when it comes to beauty routines. Yes, they can be used together. Some products contain a mix of AHAs and BHAs, such as serums from The Ordinary AHA 30% + BHA 2% Peeling Solution and Drunk Elephant’s T.L.C. Sukari Babyfacial.
A good rule of thumb is to start with one type of acid and then alternate between the two and see how your skin reacts. But as both AHAs and BHAs perform the same function, they are both effective. It comes down to a bit of trial and error to see how your skin reacts to it and what works for you.