Do I still have to pay the fee?

Cancellation fees are not unusual, nor in most instances are they unlawful. You do not state whether you cancelled within 14 days of the surgery. You asked whether you had to pay the $900. Have you been asked to pay it. You certainly have no obligation to volunteer. The amount of the fee raises the question of whether the cancellation charge is a penalty unrelated to any cost incurred by the physician or surgery center. Ever were the charge deemed lawful, I would make every effort to negotiate a much lesser sum If you can achieve a substantial reduction, it would save you the cost of retaining counsel to defend a claim were they to file one. You might want to wait and let this claim, if one has been informally made, play out a little further. However, if suit has been filed, get advice from counsel promptly.