What AHI Qualifies You for CPAP?

What AHI Qualifies You for CPAP?

Under Medicare's coverage rules, an AHI of 15 or higher qualifies you for CPAP on its own, and an AHI of 5 to 14 qualifies if you also have documented symptoms (such as excessive daytime sleepiness, impaired concentration, mood problems, or insomnia) or a documented condition such as hypertension, ischemic heart disease, or a history of stroke. Medicare applies the same thresholds to RDI, a closely related index, and many private insurers use similar criteria, though specific requirements vary by plan. The number must come from a qualifying sleep study, not from a CPAP machine or a wearable, and the decision itself belongs to your sleep physician. This page walks through where those thresholds come from and how they are applied.

Two Different Questions: Diagnosis and Coverage

"Do I have sleep apnea?" and "will insurance pay for a CPAP?" are answered by two related but separate sets of criteria, and mixing them up causes most of the confusion around qualifying numbers.

The clinical diagnosis follows the American Academy of Sleep Medicine's criteria: obstructive sleep apnea is diagnosed at 5 or more obstructive breathing events per hour when typical symptoms are present (unrefreshing sleep, daytime sleepiness, fatigue, loud snoring, witnessed pauses, gasping awakenings), or at 15 or more events per hour even with no symptoms at all. (Formally, the clinical criteria count events using RDI, a slightly broader index than AHI that also includes subtler arousals.)

The coverage decision is where the Medicare criteria in the opening paragraph come in, and they add documentation requirements the clinical definition does not have. The two-tier structure is the same (15 stands alone, 5 to 14 needs something more), but coverage requires that the "something more" be documented in your chart, not just experienced.

Your sleep study AHI	AASM severity label	Medicare CPAP coverage
Under 5	No OSA / normal	Not covered
5 to 14	Mild	Covered with documented symptoms or a qualifying condition
15 to 29	Moderate	Covered on the AHI alone
30 or higher	Severe	Covered on the AHI alone

One more layer worth knowing: Medicare's rules also set minimum event counts behind the rates. The 15-or-higher path requires at least 30 recorded events, and the 5-to-14 path requires at least 10, so a very short study with a high hourly rate but few total events may not qualify. This is one reason a borderline result sometimes leads to a repeat or longer study.

The 5 to 14 Gray Zone

If your sleep study lands between 5 and 14, the qualifying question shifts from your AHI to your documentation. The list of qualifying add-ons is specific: excessive daytime sleepiness, impaired cognition, mood disorders or insomnia, or documented hypertension, ischemic heart disease, or history of stroke.

In practice, people in this range can qualify once those factors are documented, and the symptoms that sent them to a sleep study in the first place (feeling exhausted despite a full night, a partner reporting snoring and pauses) are often the same symptoms that satisfy the requirement. The key is that they need to be written down. If your AHI comes back mild and coverage is denied, the most common fix is not a new sleep study; it is your physician documenting the symptoms or conditions that were already there. This is a conversation to have with your sleep physician, who knows exactly what the paperwork needs to say.

The Qualifying Number Comes From a Sleep Study

The AHI that qualifies you must be measured by an accepted test: an in-lab polysomnography, or a home sleep test of an approved type (Medicare accepts Type II and Type III home monitors, and Type IV monitors that record at least 3 channels). Our home sleep test guide covers what those devices measure and how to get one.

Numbers from other sources do not qualify, even when they are genuinely useful. A smartwatch flagging possible sleep apnea is a reason to get tested, not a diagnosis. And the AHI your CPAP machine reports every night is a treatment-tracking number, not a diagnostic one; it exists only after you already have the machine. The full path from suspicion to prescription is covered in how the sleep apnea diagnosis process works.

Qualifying Is the Start, Not the End

For Medicare, the initial CPAP approval is a trial that runs about 90 days. Continued coverage then depends on two things: you actually using the machine (the usage benchmark is 4 or more hours per night on 70 percent of nights in a consecutive 30-day window inside that trial) and your physician documenting that the therapy is helping. The details, deadlines, and what happens if you miss the window are in our Medicare CPAP compliance rule guide.

That is also the point where your nightly data starts to matter. Once you are on therapy, your machine reports a treated AHI each night, and the widely used benchmark for well-controlled therapy is a treated AHI under 5. What that number means and how to read it lives in our AHI explainer. If you want to see your treated AHI, usage hours, and leak together with a plain-English read of each night, you can upload your SD card data to CPAP Clarity and everything stays in your browser.

Common Questions

What AHI do you need for a CPAP machine?

Under Medicare's criteria (many private insurers use similar thresholds, though plans vary), an AHI of 15 or higher qualifies on its own. An AHI of 5 to 14 qualifies when paired with documented symptoms (excessive daytime sleepiness, impaired cognition, mood disorders, insomnia) or a documented condition (hypertension, ischemic heart disease, history of stroke). Below 5, CPAP is not covered.

Does an AHI of 10 qualify for CPAP?

It can, but not on the number alone. An AHI of 10 falls in the 5 to 14 range, which qualifies for Medicare coverage when your chart documents qualifying symptoms or conditions. If you sought testing because of symptoms, those are often the same symptoms that satisfy the requirement once they are documented. Your sleep physician makes that call.

Can my CPAP machine's AHI qualify me for coverage?

No. The qualifying AHI must come from an accepted sleep study: in-lab polysomnography or an approved home sleep test type. Your CPAP machine's nightly AHI is a treatment-tracking estimate that only exists once you already have the machine. It matters for your ongoing therapy, not for the initial qualification.

What if my AHI is under 5 but I still have symptoms?

An AHI under 5 does not meet the CPAP coverage criteria, but it does not mean your symptoms are imaginary. Sleep studies can miss subtler problems (RERAs, for example, disrupt sleep without counting toward AHI), and other sleep disorders share the same symptoms. Bring the result and your symptoms back to your sleep physician, who can decide whether further evaluation makes sense.

Is a home sleep test AHI accepted for CPAP qualification?

Yes. Medicare accepts AHI results from Type II and Type III home sleep test monitors, and from Type IV monitors that record at least 3 channels, alongside in-lab polysomnography. Home tests can run slightly lower than in-lab results because they estimate sleep time differently, which is one reason a borderline home result sometimes leads to an in-lab follow-up.

Where Your Number Leaves You

An AHI of 15 or higher qualifies you for CPAP on its own; 5 to 14 qualifies with documented symptoms or conditions; and under 5 does not qualify, though it does not end the conversation if you still feel unrested. The number must come from a real sleep study, the documentation matters as much as the rate in the mild range, and the decision runs through your sleep physician. Once you are on therapy, the question changes from qualifying to tracking, and that is where understanding your nightly AHI takes over.