What is the not allowed amount in billing terminology?

The term "not allowed amount" refers to the portion of a bill that an insurance company does not reimburse. This can happen because of various reasons such as exceeding the usual and customary rates for services, the service not being covered under the patient's insurance plan, or contractual agreements between the health care provider and the insurer limiting the reimbursements.

In billing, understanding the not allowed amount is important for both the provider and the patient, as this value directly affects what the patient may owe out of pocket. This amount is uncollectible by the provider, which is why it is distinguished from other financial obligations, like co-payments or discounts.

The other options referenced in the question pertain to different aspects of billing and patient financial responsibility. For instance, fees covered by insurance are considered allowed amounts, while patient's co-payment requirements are amounts the patient is responsible for paying at the time of service. Discounts provided to the patient reflect a reduction in the total charges but do not fit the definition of an amount that isn't reimbursed.