LCDs and NCDs: reading Medicare coverage policy before you bill

Where do Medicare's medical-necessity rules actually live?

Medicare's coverage rules sit in two searchable layers rather than a single document. National Coverage Determinations set rules that apply in every state. Local Coverage Determinations, written by the Medicare Administrative Contractor for your region, fill in everything an NCD doesn't address, and their companion billing articles spell out the supporting diagnoses and documentation. All of it is searchable in one public place: CMS's Medicare Coverage Database 1Ref 1Centers for Medicare & Medicaid Services (2026).Medicare Coverage Database (MCD) Search.That NCDs and the MACs' LCDs and billing articles are all searchable in the public Medicare Coverage Database, which is the lookup method for whether Medicare covers a service and which documentation and diagnoses a policy requires..

That database is the front door for the question "does Medicare cover this, and what does the record have to show?" It is free, it needs no login, and it returns both the national and the local policy that apply to a given service. Learning to read it is the single most useful billing habit for anyone submitting Medicare claims — including a solo practice with no billing department to ask.

NCD or LCD: which one binds you, and who wrote it

An NCD is a national rule that binds in every jurisdiction. An LCD is written by the contractor for your region and binds only its states, which means the policy that governs you depends on where you practice. Medicare claims administration is regionalized across contractors, and CMS publishes which one serves each state 2Ref 2Centers for Medicare & Medicaid Services (2026).Medicare Administrative Contractors.That Medicare claims administration is regionalized across MACs and that CMS publishes which MAC serves each jurisdiction, which is why the LCD that binds a provider depends on where they practice.. A colleague two states over may work under a different LCD, or none at all for the same service.

The practical rule that follows is to never treat another state's policy as your own. When you read about a coverage requirement in a forum or a webinar, the first question is which contractor's jurisdiction it came from. If it is not yours, it is background, not the rule you bill under.

How to read an LCD or coverage article before you bill

An LCD and its companion billing article answer three things you need before submitting a claim: whether the service is covered at all, which diagnoses support medical necessity — often an explicit list of ICD-10 codes — and what the record must document to withstand review. Your contractor's own portal publishes these policies alongside its signature and documentation guidance 3Ref 3Novitas Solutions Medicare (2026).Novitas Solutions Medicare.That a Medicare Administrative Contractor publishes its jurisdiction-specific LCDs, billing articles, and documentation and signature guidance on its own portal, which is where a provider reads the policy that binds their region..

Work backward from the article. Match the diagnosis on your claim to the codes the policy actually supports; if the code you would naturally use isn't on the list, that is a denial waiting to happen, not a formatting quibble. Then keep the specific documentation the article names — frequency, prior conservative care, a functional finding — because a reviewer checks the note against the policy, not against your clinical intent.

Where reasonable-and-necessary is actually defined

Behind every NCD and LCD sits the statutory standard that Medicare pays only for services that are reasonable and necessary. That standard, and the program-wide instructions built on it, live in CMS's Internet-Only Manuals — chiefly the Benefit Policy Manual and the Claims Processing Manual — which are the operative instructions a contractor applies when it adjudicates your claim 4Ref 4Centers for Medicare & Medicaid Services (2026).Internet-Only Manuals (IOMs).That CMS program instructions live in the public Internet-Only Manuals — including the Benefit Policy Manual and the Claims Processing Manual — which are the operative instructions a contractor applies, and where the reasonable-and-necessary standard is anchored..

The manuals matter most in the gaps. An LCD can be specific about one service and silent about another, but the general reasonable-and-necessary standard governs either way. When a policy doesn't resolve your question, the manual chapter usually does, and citing the manual is stronger footing than citing a summary of it — this is where a definition of medical necessity is anchored rather than paraphrased.

What happens when there's no LCD or NCD

No written policy is not the same as automatic coverage. When neither an NCD nor an LCD addresses a service, the contractor still decides each claim against the reasonable-and-necessary standard, using clinical judgment case by case 4Ref 4Centers for Medicare & Medicaid Services (2026).Internet-Only Manuals (IOMs).That CMS program instructions live in the public Internet-Only Manuals — including the Benefit Policy Manual and the Claims Processing Manual — which are the operative instructions a contractor applies, and where the reasonable-and-necessary standard is anchored.. The absence of a policy means less predictability, not a guarantee — and you carry the same documentation burden you would under an explicit LCD.

So when you search the Medicare Coverage Database and find nothing on your service, the honest read is "undetermined," not "yes" 1Ref 1Centers for Medicare & Medicaid Services (2026).Medicare Coverage Database (MCD) Search.That NCDs and the MACs' LCDs and billing articles are all searchable in the public Medicare Coverage Database, which is the lookup method for whether Medicare covers a service and which documentation and diagnoses a policy requires.. Build the necessity record as if a policy required it: a clear indication, the diagnosis that drives it, and the response that justifies continuing. A frequency question — how often twice-weekly therapy is supportable, for instance — often has no bright-line national answer, which is exactly when your documentation has to carry the weight.

Coverage has two questions, not one

A service can be fully covered and still be denied because you are not an eligible biller for it. Medicare coverage turns on both the service and the provider type, and those rules move. The program's behavioral-health materials, for example, list which clinicians may bill which codes — a set that widened when marriage-and-family therapists and mental-health counselors became eligible to enroll and bill 5Ref 5Centers for Medicare & Medicaid Services (2025).Medicare and Mental Health Coverage.That Medicare coverage depends on provider type as well as the service — the booklet lists eligible provider types and covered codes, including that marriage-and-family therapists and mental-health counselors became eligible to enroll and bill.. Confirm both before you submit.

This is where solo clinicians in newer eligible professions get caught: the code is covered, the diagnosis supports it, the note is clean — and the claim still bounces because enrollment or provider-type eligibility wasn't in place. Verify that you can bill the code, not only that the code exists. Couples work and other service-specific coverage quirks live in the same place, service by service.

When you expect a non-coverage: the ABN

When you have reason to believe Medicare will deny a service as not reasonable and necessary, the Advance Beneficiary Notice of Noncoverage is how you tell the patient in writing beforehand and preserve your ability to bill them if Medicare declines. Without a valid ABN signed before the service, you generally cannot hold the patient responsible for a denied item. CMS publishes the form and its instructions 6Ref 6Centers for Medicare & Medicaid Services (2026).Beneficiary Notices Initiative (BNI).That the Advance Beneficiary Notice of Noncoverage and its instructions are published under CMS's Beneficiary Notices Initiative, and that a valid ABN is required before billing a Medicare patient for a service likely to be denied as not reasonable and necessary..

The ABN is the honest bridge between a policy you can't meet and getting paid without surprising the patient. It is not a workaround for skipping the coverage check — you still read the LCD first. It is what you use when the read comes back "probably not covered" and the patient wants the service anyway, on paper, with eyes open.

A lookup workflow before you submit

Turning all of this into a habit takes about five minutes and five steps you can run before a claim ever leaves your practice. Each step maps to one of the authorities above, so the workflow is portable to any service and any Medicare patient.

• Search the service in the Medicare Coverage Database for an NCD or your contractor's LCD and billing article 1Ref 1Centers for Medicare & Medicaid Services (2026).Medicare Coverage Database (MCD) Search.That NCDs and the MACs' LCDs and billing articles are all searchable in the public Medicare Coverage Database, which is the lookup method for whether Medicare covers a service and which documentation and diagnoses a policy requires..
• Confirm which contractor and jurisdiction you fall under, since the local policy depends on it 2Ref 2Centers for Medicare & Medicaid Services (2026).Medicare Administrative Contractors.That Medicare claims administration is regionalized across MACs and that CMS publishes which MAC serves each jurisdiction, which is why the LCD that binds a provider depends on where they practice..
• Match your claim's diagnosis to the codes the article supports, and keep exactly the documentation the article names 3Ref 3Novitas Solutions Medicare (2026).Novitas Solutions Medicare.That a Medicare Administrative Contractor publishes its jurisdiction-specific LCDs, billing articles, and documentation and signature guidance on its own portal, which is where a provider reads the policy that binds their region..
• Verify you are an eligible biller for the code, not only that the code is covered 5Ref 5Centers for Medicare & Medicaid Services (2025).Medicare and Mental Health Coverage.That Medicare coverage depends on provider type as well as the service — the booklet lists eligible provider types and covered codes, including that marriage-and-family therapists and mental-health counselors became eligible to enroll and bill..
• If you expect a non-coverage, get a valid ABN signed before the service, using CMS's current form 6Ref 6Centers for Medicare & Medicaid Services (2026).Beneficiary Notices Initiative (BNI).That the Advance Beneficiary Notice of Noncoverage and its instructions are published under CMS's Beneficiary Notices Initiative, and that a valid ABN is required before billing a Medicare patient for a service likely to be denied as not reasonable and necessary..