Three Midnight Rule Medicare SNF Washington

The Rule That Determines Whether Medicare Pays for Rehab

Your parent just had hip surgery and the doctor says they need several weeks of rehabilitation at a skilled nursing facility before going home. Medicare Part A covers SNF stays — but under the standard rule only if the patient first has at least three consecutive inpatient days in an acute care hospital.

This is the three-midnight rule, and it is the single most consequential qualification gate for Medicare-covered rehabilitation in Washington State. Miss it by one midnight, and the entire SNF stay shifts to the patient's pocket.

How the Count Works

Medicare counts the day of inpatient admission and excludes the day of discharge. Families often call this the three-midnight rule, but the operative test is at least three consecutive inpatient days. Here is how the count operates:

The admission day counts. If your parent is admitted as an inpatient at 11:00 PM on Monday, Monday is the first countable inpatient day.

Discharge day does not count. If the patient is discharged on Thursday morning, count Monday, Tuesday, and Wednesday when those are the three consecutive inpatient days; do not count Thursday as a qualifying day.

The inpatient days must be consecutive. A break in the inpatient stay can interrupt the qualifying sequence; ask the hospital how any discharge and readmission will be counted.

A practical example: a patient admitted Tuesday evening who remains inpatient through Friday morning has three qualifying inpatient days (Tuesday, Wednesday, and Thursday). They meet the standard threshold and can transfer to a Medicare-covered SNF if the other coverage requirements are met.

Observation Hours Do Not Count

This is the critical catch. Hours spent under observation status — even if the patient is in a hospital bed receiving active medical care — do not count toward the three-midnight requirement. Observation status is classified as outpatient care under Medicare Part B, and outpatient hours have no bearing on the SNF qualification threshold.

A patient can spend four days under observation, receive extensive treatment, and transfer to a skilled nursing facility — and under standard Original Medicare, Medicare will not cover a single day of the SNF stay because the qualifying inpatient-day threshold was never met.

In Washington, the average private-pay cost for a skilled nursing facility exceeds $14,000 per month. That is the bill facing families whose parent needed the observation hours classified as inpatient but did not get that classification. If this happens, the family's options narrow to paying out of pocket, applying for Medicaid (a 45–90 day process with strict asset limits), or appealing the observation status classification.

What Medicare Covers Once the Threshold Is Met

When the three-midnight requirement is satisfied, Medicare Part A covers up to 100 days of skilled nursing facility care per benefit period:

• Days 1–20: Medicare pays 100% of covered services
• Days 21–100: The patient pays a daily coinsurance ($217 in 2026), and Medicare covers the remainder
• After day 100: Medicare coverage ends, and the patient is responsible for the full cost

The SNF admission must occur within 30 days of the qualifying hospital stay. If the patient goes home and then enters the SNF 35 days later, the three-midnight qualifying stay no longer applies.

The care must also be skilled — meaning the patient requires daily skilled nursing or skilled rehabilitation services (physical therapy, occupational therapy, speech therapy) that can only be provided in an SNF setting. Custodial care alone does not qualify.

How to Track the Count in Real Time

Families should not rely on the hospital to track this for them. The discharge planner is managing dozens of patients, and the distinction between inpatient and observation status is a billing classification that does not always surface in bedside conversations.

Track it yourself:

1. Ask on admission: "Is my parent admitted as an inpatient or placed under observation?" Get a clear answer and write down the date and time.

2. Confirm each inpatient day. At the end of each day, verify that the patient's status has not changed. Hospitals can reclassify a patient from inpatient to observation retroactively — sometimes days into the stay.

3. Document everything. Keep a simple log: admission date/time, each qualifying inpatient day, any status changes, and the names of staff members who confirmed the classification.

4. Watch for the MOON. If the hospital delivers a Medicare Outpatient Observation Notice (Form CMS-10611), your parent is under observation and those inpatient days are not counting. If a Medicare Change of Status Notice (Form CMS-10868) appears, the hospital has reclassified the stay — and you have appeal rights.

When the SNF Transfer Happens

If the three-midnight threshold is met and the patient needs rehabilitation, the hospital discharge planner should coordinate the transfer. In Washington, key factors to evaluate when choosing an SNF include:

• Medicare certification. The facility must be Medicare-certified to bill Part A for the SNF stay.
• Medicaid contract. If the patient's rehabilitation extends beyond what Medicare covers, a facility with a Medicaid contract provides a transition pathway without requiring a move.
• Staffing. Washington requires nursing homes to provide a minimum of 3.4 hours of direct care per resident day under WAC 388-97-1090. Ask the facility for their current staffing ratio.
• Inspection history. Check the facility's record through the DSHS Residential Care Services lookup tool (fortress.wa.gov) and Medicare's Care Compare.

Do not accept the first facility the discharge planner suggests without reviewing its inspection history. The discharge planner has a legal obligation under RCW 70.41.320 to provide options, not just a single recommendation.

What to Do If the Threshold Is Not Met

If your parent is under observation status or the inpatient stay falls short of three qualifying inpatient days, you have several paths:

Ask the attending physician to extend the inpatient stay. If the patient's clinical condition justifies continued inpatient care, the physician can choose to keep them admitted. The three-midnight clock continues running.

Appeal a reclassification. If the hospital reclassified your parent from inpatient to observation, file an expedited appeal with Acentra Health (1-888-305-6759), Washington's BFCC-QIO. If the reclassification is overturned, the observation hours are retroactively counted as inpatient days.

Consider self-pay or Medicaid. If the threshold is genuinely not met, the SNF stay will not be covered under standard Original Medicare. The family can pay the private rate, negotiate a reduced rate with the facility, or begin a Medicaid application through DSHS — though the application process typically takes 45 to 90 days.

The Hospital-to-Home Transition Guide includes a three-midnight tracking sheet designed for families to monitor each qualifying inpatient day in real time, plus the appeal scripts and SNF contract audit checklists that help families avoid signing agreements that create personal financial liability for a parent's care costs.

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