Medicare Part A covers up to 100 days of care in a nursing home per 'benefit period,' but only if you meet strict criteria: a 3-night inpatient hospital stay and a need for daily skilled therapy or nursing. The first 20 days cost $0, but days 21 through 100 require a daily co-pay of $204 (in 2024). If the resident stops making measurable progress toward a goal, Medicare can—and will—terminate coverage long before day 100.

To unlock the 100-day benefit, a person must be an 'inpatient' in a hospital for at least three consecutive midnights. This sounds simple, but hospitals frequently place people under 'observation status' to avoid federal penalties for readmissions. You can be in a hospital bed, eating hospital food, and wearing a hospital gown for five days without ever being officially 'admitted.' If the paperwork says observation, the 100-day clock never starts, and the nursing home stay will be 100% out-of-pocket.

Ask the hospital social worker point-blank: 'Is my parent an inpatient or here for observation?' If it is the latter, you need to advocate for a status change immediately, though hospitals are often reluctant to do so. This distinction is the difference between a covered recovery and a financial catastrophe that drains a savings account in a month.

Time spent in the ER does not count toward your three midnights. Neither does the day you are discharged from the hospital. You need three full nights of inpatient status before the nursing home door opens, or you are effectively writing a blank check to the facility.

The '100 days' phrasing is the most successful bit of marketing the government ever produced. It implies a century of safety, but the full coverage ends abruptly on day 20. On day 21, the resident is responsible for a daily co-pay of $204. Over the remaining 80 days of the benefit, that adds up to $16,320. If you have a Medigap policy (Medicare Supplement), it usually covers this co-pay, but if you are on straight Medicare or certain Advantage plans, that bill is yours.

Medicare Advantage plans (Part C) often complicate this further. While they must cover the same benefits as original Medicare, they frequently require 'prior authorization' every few days. You might think you are set for 100 days, only to have the Advantage plan representative call on day 14 to say they are cutting off funding because your father can now walk ten feet with a walker. They don't care if he can't get into a car or cook a meal; they care if he is 'stable.'

When choosing a nursing home for this 100-day window, do not rely on the glossy brochures provided by referral sites like A Place for Mom or Caring.com. Those platforms are paid commissions by the facilities they recommend and often omit those that don't pay for leads. Instead, look at federal CMS and state inspection data. A facility might have a five-star lobby and a one-star safety record for falls and pressure sores. We use this data to calculate the Palmelle Clarity Score because the math doesn't lie, even when the marketing does.

One of the most common reasons people get kicked out of nursing homes before day 100 is the 'plateau' myth. Staff might tell you that because your mother isn't getting better anymore, Medicare will no longer pay. This was actually debunked by a federal court case (Jimmo v. Sebelius). Medicare is required to pay for skilled care to *maintain* a person's condition or to prevent further decline, not just for improvement.

If the facility issues a 'Notice of Non-Coverage' (a fancy way of saying they are cutting you off), you have the right to an immediate expedited appeal. The instructions are on the back of that notice. Do not sign it and simply leave. If you appeal, the Quality Improvement Organization (QIO) will review the case, and coverage usually continues during the 24-48 hours the appeal is being processed.

Be aware that the nursing home is a business. Once the Medicare money stops, they want that bed filled by another Medicare resident (who pays more) or a private-pay resident (who pays the most). They have a financial incentive to tell you the 100 days are up. Your job is to know the data, check the Palmelle Clarity Score for the facility's history of involuntary discharges, and push back when the 'plateau' excuse is used.