Most denied SNF stays are not denied at billing. They are decided at admission, in the fifteen minutes someone spent — or did not spend — confirming what the patient's coverage actually was. Verification is the cheapest point in the entire revenue cycle to catch a problem, and the most expensive point to skip.
Verification decides denials
By the time a claim is denied, the patient has been in the building for weeks. The care was delivered, the staffing was paid for, and the options are appeal or write-off. Nothing in the back half of the revenue cycle recovers the margin lost by admitting a patient whose coverage was terminated, whose benefit days were exhausted, or whose plan required an authorization nobody requested.
The verification step exists to answer four questions before the patient arrives:
- 1Is coverage active on the anticipated admission date?
- 2Which payer is actually primary, and is there secondary coverage behind it?
- 3Does this plan cover skilled nursing at this level, and for how many days?
- 4Is prior authorization required, and who obtains it?
A referral packet answers none of these reliably. The insurance card in the packet is a photocopy of what the patient had when they were admitted to the hospital, which may be weeks old and was frequently wrong when it was taken.
How an eligibility check works
Underneath every verification method — payer portal, clearinghouse, phone call — sits the same standardized transaction pair. The provider sends an X12 270 eligibility inquiry identifying the patient and the coverage being asked about; the payer returns an X12 271 response describing what it knows.
The 271 is where the useful detail lives. It carries eligibility and benefit segments that can include the plan type, active or inactive status, copay, coinsurance and deductible amounts, benefit period information, and — for Medicaid members — the managed care organization the member is assigned to. Reading that response correctly is a real skill, because payers use the same fields differently.
Two payers can return "active coverage" in the same field and mean materially different things. The segment layout is standardized; how payers populate it is not.
This is why a verification workflow that just screenshots a portal page tends to fail quietly. The screenshot proves someone looked. It does not capture the plan type, the benefit days, or the authorization requirement in a form anyone can act on later.
Traditional Medicare
Part A skilled nursing coverage carries conditions that are well defined and routinely missed:
- The qualifying hospital stay. Traditional Medicare generally requires a preceding inpatient hospital stay of at least three consecutive days, not counting the day of discharge. Observation status does not count toward it — a distinction that has caused an enormous number of unexpected non-covered admissions. Confirm the patient's status, not just their dates.
- Benefit period days. A benefit period provides up to 100 days of SNF coverage, with the first 20 days paid in full and days 21 through 100 subject to a daily coinsurance amount that CMS sets each year. Verify the days already used — patients transferring from another facility frequently arrive with a partially consumed benefit period.
- Benefit period reset. A new benefit period begins after the patient has been out of a hospital or SNF for 60 consecutive days. Readmissions inside that window continue the prior benefit period rather than starting a fresh 100 days.
- Skilled level of care. Coverage requires daily skilled nursing or skilled therapy services. Custodial need alone is not covered regardless of how many benefit days remain.
Also confirm the Medicare Beneficiary Identifier. The MBI replaced the old SSN-based claim number, and referral packets still surface stale or mistyped identifiers. A transposed character produces a failed eligibility response that looks, to an untrained eye, exactly like a terminated policy.
Medicare Advantage
An MA plan replaces Traditional Medicare as the payer, and the operational differences are significant enough that treating MA as "Medicare with extra paperwork" is a reliable way to lose money.
| Traditional Medicare | Medicare Advantage | |
|---|---|---|
| Prior authorization | Not required for SNF admission | Almost always required |
| Length of stay | Governed by benefit period and skilled need | Authorized in short increments, concurrently reviewed |
| Network | Any participating provider | Contracted network, out-of-network rules vary |
| Rate | PDPM case-mix rate | Contracted rate, often a negotiated per diem |
| 3-day stay | Generally required | Frequently waived by the plan |
MA plans must provide at least the coverage Traditional Medicare provides, and CMS rules constrain the use of internal criteria more restrictive than Medicare's. In practice, plans still authorize in increments and review concurrently, so the operational reality is that the authorization — not the eligibility check — is what protects payment. An active MA policy with no authorization on file is an uncovered stay.
Practical rule
Medicaid and managed Medicaid
Medicaid is not one payer; it is fifty-some programs that share a name. Eligibility rules, the level-of-care determination process, patient liability calculation, and the managed care landscape all vary by state, and the 271 responses vary with them.
Three things to establish on every Medicaid referral:
- Fee-for-service or managed? A member enrolled in a Medicaid managed care organization is that MCO's responsibility, not the state's, and the MCO usually has its own authorization process. The MCO assignment is often returned in the eligibility response, but the segment used to convey it differs by state — and in some states it is not returned at all, so a portal check is required.
- Patient liability. The member's share of cost, sometimes called applied income or patient pay amount, reduces what Medicaid pays. It changes with the member's circumstances and should be re-verified, not carried forward from the referral.
- Pending applications. Many long-term-care admissions arrive with a Medicaid application in process rather than approved. That is a business decision, not a verification result — but it needs to be recorded as pending so nobody downstream assumes coverage exists.
Seven traps that cause denials
- 1Trusting the hospital's copy. The face sheet reflects coverage at hospital admission. Plans change, especially around January 1 and during annual enrollment.
- 2Verifying once. Coverage verified three days before admission can be terminated on the day of admission. Re-verify on the admission date and periodically during the stay.
- 3Missing the secondary. Teams verify the primary, admit, and discover the secondary months later. Establish the full coverage picture up front, including any Medicare supplement.
- 4Reading "active" as "covered." Active enrollment says nothing about whether this benefit, at this level of care, in this setting, is payable.
- 5Ignoring the request-date echo. Some payers return the date you asked about rather than the date coverage was confirmed for. Verifying for the wrong date and reading back your own input is a subtle and common failure.
- 6Recording a payer name instead of a payer. "Blue Cross" is not a payer. The specific plan, product line and network determine both coverage and rate.
- 7Logging patient errors as payer failures. When a wrong member ID produces an error, teams often note the payer as unresponsive. Do this enough and the team stops trusting a payer that was never the problem.
A verification checklist
Whatever tooling you use, the record you keep should answer these without anyone reopening a portal:
- Payer, specific plan and product line, and whether it is in network
- Member ID as verified, not as transcribed from the referral
- Coverage status and the effective date range
- Benefit days used and remaining, where applicable
- Prior authorization requirement, submission channel and reference number
- Copay, coinsurance, deductible or patient liability
- Secondary coverage, or an explicit note that none was found
- Date, time and method of verification, and the raw response retained
The last item is the one teams skip and later regret. When a payer disputes what they told you, the retained response is the entire argument. Automated eligibility checking earns much of its value simply by keeping that record consistently, on every referral, without anyone remembering to.
And because verification runs independently of clinical review, it should start the moment a referral arrives rather than after the nurse decides — one of the highest-leverage changes available to an admissions team, as covered in cutting referral response time.