The market rate for a therapist these days is something like $250/hour here in the bay area. Many insurance plans will reimburse if you submit an invoice from a therapist. The reimbursement rates vary greatly, sometimes zero, sometimes 50%, sometimes 80%, etc.
So all that to say that it's a super shitty system where you can't know ahead of time how expensive therapy will end up being for you, and the therapists themselves typically also don't know ahead of time (although they can certainly have a sense of which insurance companies typically reimburse at different rates).
Source: my wife is a psychologist in SF who doesn't directly accept insurance but the majority of her patients receive some level of insurance reimbursement.