Question: California Subscriber Answer: Although we don't know the specifics of your case, we'll assume three truths: (1) The doctor has no contract with Payer A or Payer B, (2) The plans are not Medicaid plans, and (3) These are not HMO Plans under a state no balance billing HMO law. In addition, we aren't sure the original charge amount that you billed at the outset. However, in most cases, the patient does owe you the amount that was applied to the deductible. But depending on the variables (contract, Medicaid, state HMO no balance billing law), then the patient may also owe the difference between charges and payment. For example: If the doctor is non-par, the patient owes what his insurance plans didn't pay up to the amount of the doctor's charges, whether it's an "applied to deductible" situation or not. This becomes more complicated if the doctor is contracted because you would need to see the contract language. If the plans are Medicaid payers or if there is a no-balance billing law, it is even more complicated.