How Medicare Part B Reimbursement Works for SNFs

If you run revenue cycle inside a skilled nursing facility, you already know Medicare Part A. The PDPM rate is consolidated, the cut-off is clean, and your billers can quote the per-diem in their sleep. Medicare Part B is the opposite: a fee-for-service program built around thousands of individual HCPCS and CPT codes, each with its own coverage rules, modifier requirements, and Local Coverage Determination (LCD). That complexity is exactly why most SNFs leave six-figure Part B revenue on the table every year.

This guide walks through the entire reimbursement chain — from the moment a nurse documents a supply in PointClickCare to the day the Electronic Remittance Advice (ERA) lands in your bank account. We'll cover who can bill, what gets paid, how the math works, where claims die, and how to forecast recoverable revenue before you submit a single claim.

What Medicare Part B actually covers in an SNF

Part B is the outpatient benefit. Inside a nursing facility, it pays for medically necessary supplies and services delivered to residents who are not in an active Part A skilled stay. That includes long-term care residents, residents who have exhausted their 100 Part A days, and residents in custodial status. The most common reimbursable categories are:

• Urological supplies — intermittent catheters (A4351–A4353), drainage bags, irrigation kits
• Ostomy supplies — pouches, barriers, accessories (A4361–A4434)
• Surgical dressings — primary/secondary dressings under LCD L33831
• Enteral nutrition — formula, pumps, supply kits (B4034–B4088, B9000–B9002)
• Diabetic supplies — test strips, lancets, glucose monitors (A4253, E0607, E2100)
• Respiratory & nebulizer drugs — J7613, J7626, J7644 and related J-codes paid at ASP + 6%
• Select DME — CPAP, walkers, wheelchairs, hospital beds where the resident retains medical necessity outside Part A

If you want the full coding-level breakdown, see our Medicare Part B Supply List for SNFs and the SNF CPT Codes reference.

Who is allowed to bill Part B for SNF residents

This is the question every facility gets wrong at least once. Part B supplies for SNF residents should be billed by the facility, under its own NPI, to the appropriate Medicare Administrative Contractor (MAC) or DME MAC. The facility owns the CMS relationship, owns the reimbursement, and owns the audit obligation. When a vendor bills under their NPI and ships into your building, that revenue leaves the facility — and so does the audit defense if anything goes wrong.

The four-step claim lifecycle

Every Part B supply claim moves through the same four phases. Break the chain anywhere and the claim either denies, pends for additional documentation, or — worst case — pays now and gets recouped on audit later.

1. Order. A treating physician issues a Standard Written Order (SWO) that meets the controlling LCD's medical-necessity criteria. The order must precede or coincide with dispensing.
2. Document & dispense. The supply is dispensed to the resident and the event is captured in the clinical record: nurse charting, MAR entry, eMAR/POC export, and (for DMEPOS) Proof of Delivery (POD) with resident signature.
3. Submit. The claim is built under the facility's NPI with the correct HCPCS code, unit count, modifiers (KX, GA, GZ, RT/LT, etc.), and ICD-10 diagnoses from the LCD-covered list, then routed to the right MAC or DME MAC.
4. Adjudicate. CMS pays via ERA, denies with a CARC/RARC reason code, or pends with an Additional Documentation Request (ADR). Clean claims pay in roughly 14–30 days under the Prompt Payment Act.

How the fee schedule actually pays

Part B reimbursement isn't 'whatever you bill.' Each HCPCS code has a defined allowed amount on either the Part B Physician Fee Schedule (PFS) or the DMEPOS Fee Schedule, geographically adjusted by your MAC jurisdiction. Medicare pays the lower of your submitted charge or the fee-schedule allowed amount, then splits it 80% to the facility and 20% to the resident or their Medigap policy. Drugs are reimbursed at Average Sales Price (ASP) + 6%, updated quarterly by CMS.

For the full lookup workflow, including how to read CMS fee-schedule files and adjust for your locality, see our Medicare Fee Schedule for SNFs resource and the Medicare Billing Units primer.

Why most SNFs leave 70%+ of Part B on the table

Three structural reasons, in roughly the order we see them when we audit a new facility's prior 12 months of utilization:

The pattern is consistent across building sizes and EHRs. Part B reimbursement isn't lost because facilities are sloppy — it's lost because Part B billing requires sub-specialty expertise that doesn't economically fit on a general business-office team. A facility that bills 200 Part A claims a month might only have 30 eligible Part B residents at any given time, and each of those claims requires code-level knowledge most billers learn once a year, if that.

Forecasting recoverable revenue before you bill

Here's the underwriter's shortcut. Pull a 90-day census of long-stay and post-A residents, multiply by an industry-average supply utilization per resident-day for each category, apply your MAC's fee-schedule rate, and you have a defensible upper bound on what Part B should be producing for your building. Then compare that to your actual 90-day Part B remittance. The delta is your recoverable revenue, expressed in dollars CMS is willing to pay if the documentation supports the claim.

What it takes to actually capture it

Three things, every claim, every time: a defensible clinical record, a code-correct claim, and a billing partner who carries the audit obligation with you. The chart has to support medical necessity, the HCPCS / modifier / units have to be right, and somebody has to be on the hook when a RAC or TPE letter arrives. If any one of those three is missing, the revenue either never lands or gets clawed back later.

That's the model Burst Billing runs: documentation-first, billed under your NPI, contingency-only, with audit response included on every claim we touch. If you want to see what your building's recoverable Part B looks like against your own utilization data, book a no-cost reimbursement review.