My deductible is only $500, and I hit that within one month since I see the therapist 2x/week. Once I meet the deductible, I have to pay $25 + 10%. My plan actually specifies +20%, but I noticed the therapist isn't charging that. She didn't say anything about it, though. I hit the out of pocket limit about 1.5 months before everything resets. At that point, I don't have to pay a copay anymore and insurance pays everything.

Insurance never pays what therapists actually bill. Additionally, there are all sorts of weird intricacies to billing that can sometimes change the rate. For example, we had insurance previously that would start paying the therapist more after a certain number of sessions every year. I don't think it's your responsibility to worry about your therapist's billing. Your responsibility is just to render payment as agreed.

I would expect a therapist to inform me if they were planning on not taking my insurance anymore. If I was paying out of pocket, I would expect to be notified a couple months in advance of any change in fees. When I was seeing a psychiatrist who didn't take insurance, that is how it was done at the agency where she worked. If I was just paying a copay, I'm not sure if I would expect to be informed. On one hand, I really wouldn't care because it wouldn't affect me. However, for people who have really high deductibles, a change in fees is something they might want to know about - even if they've met the deductible for the current year. I am a student and don't have a lot of money. Even though my deductible is really low as deductibles go, I still have to plan for it, since $500 is unfortunately about half a month's income for me. So I think there could be good reasons to let clients know about changes in fees - maybe not small $10 ones, but $50 is a 30% increase from your therapist's previous fee.