There's co-pay and co-insurance. Co-pay is what your insurance company determines based on your plan. Could be $20, $30 or more. And then there is co-insurance which is the percentage of allowable charges not covered under your plan. For most of the best plans, co-insurance is 20% of what insurance allows for the rate.

So, what you owe (patient responsibility) depends on the amount of your co-pay, plus co-insurance under your plan. It sounds like your previous plan didn't have a co-pay, just the co-insurance, so that's why you could owe more now and your therapist may be right. Only your insurance company can tell you for sure. Also, the amount this insurance allows may be different as well.