How to issue an Advance Beneficiary Notice

The Advance Beneficiary Notice of Noncoverage (ABN), issued on the CMS-standardized Form CMS-R-131, is used in Original (fee-for-service) Medicare Part B to tell a beneficiary in advance that Medicare is expected to deny payment for an item or service, so the person can make an informed choice about receiving it and accepting financial responsibility. It is a mechanism tied to Medicare's limitation-on-liability provisions: when a valid ABN is on file, financial responsibility can shift to the beneficiary if Medicare denies the claim. Without a proper ABN, the provider may be unable to bill the beneficiary for a denied service.

An ABN is generally appropriate where a service Medicare usually covers is expected to be denied in a specific instance — most commonly for lack of medical necessity, frequency limits, or coverage criteria expressed in a national or local coverage determination. It is not the right notice for services Medicare never covers as a statutory matter, though a voluntary ABN may still be used to inform the beneficiary in those situations. The ABN applies to Original Medicare; Medicare Advantage (Part C) plans use their own organization-determination and denial-notice processes, so the ABN process described here does not govern those plans.

Whether an ABN is required, permitted, or unnecessary depends on the item, the coverage rule in play, and contractor guidance. Because the triggering rules vary by service and can change over time, the applicable coverage determination and current CMS instructions should be confirmed rather than assumed. Related concepts worth understanding first include medical necessity, local coverage determinations, and the general shape of Part B billing.

The ABN is a structured form with defined blanks that must be completed before delivery. Core fields identify the notifier (the provider or supplier), the beneficiary, and the specific item or service at issue. The form requires a plain-language description of the item or service, the reason Medicare is expected to deny it, and an estimate of the cost the beneficiary may owe. The reason and cost-estimate fields exist so the beneficiary can weigh the decision, so they should be specific to the situation rather than generic boilerplate.

The form presents the beneficiary with options for whether to receive the service and whether the provider should submit a claim to Medicare anyway. The beneficiary selects one option, signs, and dates the notice. The notice must be legible, must not be altered after signing, and must genuinely give the beneficiary a real choice — pre-selecting an option on the beneficiary's behalf undermines validity. CMS specifies formatting expectations for the form, including limits on how it may be reproduced.

CMS distributes the official form and completion instructions through its notices program; the current file and any language or accessibility versions should be obtained from CMS rather than recreated from memory. Cost estimates are expectations, not guarantees, and the manner in which they must be expressed is defined by CMS instructions. Because these details are governed by federal guidance that is updated periodically, the operative CMS instructions should be treated as controlling.

An ABN must be delivered far enough in advance that the beneficiary has time to consider the options and ask questions before the service is furnished — not handed over at the moment of service as a formality. Delivery is to the beneficiary or an authorized representative, and the person delivering it should be prepared to explain the notice and answer questions. CMS guidance addresses timing expectations, delivery to representatives, and situations such as repetitive or continuous services; those specifics should be confirmed against current instructions rather than presumed.

After the beneficiary selects an option and signs, a copy is provided to the beneficiary and the original is retained in the practice's records. The signed ABN is the evidence that supports later billing of the beneficiary if Medicare denies the claim, so retention and retrievability matter. Record-retention periods are governed by CMS and other applicable requirements and can vary, so the retention rule in force should be verified.

Front-end processes such as eligibility verification and confirming coverage details can surface, before the visit, the situations where an ABN is likely to be needed. Building the ABN check into intake reduces last-minute delivery and improves the quality of the beneficiary's decision. When an ABN is missed and Medicare denies the service, the financial responsibility may fall to the provider rather than the beneficiary.

When the service is furnished and a claim is submitted, Medicare uses claim-level indicators to know whether an ABN is on file and what the beneficiary decided. CMS defines specific HCPCS modifiers that communicate whether a signed ABN exists, whether the notice was voluntary, and whether the item is statutorily excluded; the correct modifier depends on the ABN scenario. Using the modifier that matches the actual notice on file is what allows Medicare to adjudicate liability correctly, so the modifier selection should follow current CMS instructions for the situation.

If the beneficiary chose to have a claim submitted, the claim proceeds and the remittance advice will indicate the payment or denial outcome; reading that remittance correctly determines whether the beneficiary can be billed. If the beneficiary declined the service, no claim for it is submitted. Where a denial occurs and a valid ABN supports beneficiary liability, the balance can be billed to the beneficiary consistent with Medicare rules; where no valid ABN exists, the denial may become a provider write-off.

Because modifier definitions, claim-format requirements, and adjudication rules are maintained by CMS and its contractors and are periodically revised, the current CMS Claims Processing guidance and the relevant contractor instructions should be consulted for exact usage. This keeps ABN handling aligned with both the notice program and downstream denial and appeal processes.