ICD-10 Code for Sleep Apnea: G47.33 and What It Means
If you came here for the short answer, here it is. The ICD-10 code for obstructive sleep apnea is G47.33. It applies to both adults and children, and it is the code your doctor or sleep clinic almost certainly used when they entered your diagnosis into a medical record or submitted a claim to your insurer.
That is the answer most people are looking for. But the code itself raises a few questions worth understanding, especially if you are reading this because you spotted it on a sleep study report, a referral, or an explanation of benefits and wondered what it actually represents. So I want to slow down and explain what G47.33 covers, how it sits alongside the other sleep apnea codes, and why the difference between two very similar codes can decide whether your CPAP machine gets covered.
Before I go further, a disclosure that matters on a page like this. My background is in computer science, not medicine and not medical coding. I have lived with severe obstructive sleep apnea for more than a decade, so I have spent a long time on the patient side of this system, but I am not a certified coder, and I am not telling you how to bill a claim. I am based in Western Australia, and Australia uses a different version of the system called ICD-10-AM, so the exact codes I encounter on my own paperwork are not identical to the ones in this article. Everything here is the American ICD-10-CM version, which is what almost everyone searching for these codes wants. I verified every code below against the official source, and I will point you to that source so you can check any of them yourself.
What G47.33 actually covers
G47.33 is the billable diagnosis code for obstructive sleep apnea in adults and children. It lives in the section of ICD-10-CM that deals with diseases of the nervous system, under the broader heading of sleep disorders, and it has been valid and in use since the United States moved from ICD-9 to ICD-10 back in 2015. For the current fiscal year it remains valid for dates of service from October 1 through the following September 30, the window the coding system updates on each year.
Here is the part that surprises a lot of patients. There is no separate code for mild, moderate, or severe obstructive sleep apnea. One code covers the entire range. My own diagnosis was severe, with an apnea hypopnea index of 51 at the time of testing, and someone with a far milder case carries the exact same diagnosis code I do. The severity lives in the clinical documentation behind the code, in the apnea hypopnea index and the notes from your sleep study, not in the code number itself. This matters more than it sounds like it should, because the supporting documentation is what insurers actually read when they decide whether to pay for treatment.
If you want the clinical picture of the condition that G47.33 represents, I cover that separately in my piece on obstructive sleep apnea. For this page the important thing is simply that G47.33 is the single, specific code for the obstructive form, the most common type by a wide margin.
The full family of sleep apnea codes
G47.33 does not exist on its own. It sits inside a small group of codes under G47.3, and knowing the neighbors helps you understand why the obstructive code is the one you usually see. Every code in this group is current for the fiscal year and verified against the official tabular list.
| Code | Description |
|---|---|
| G47.30 | Sleep apnea, unspecified |
| G47.31 | Primary central sleep apnea |
| G47.32 | High altitude periodic breathing |
| G47.33 | Obstructive sleep apnea (adult) (pediatric) |
| G47.34 | Idiopathic sleep related nonobstructive alveolar hypoventilation |
| G47.35 | Congenital central alveolar hypoventilation syndrome |
| G47.36 | Sleep related hypoventilation in conditions classified elsewhere |
| G47.37 | Central sleep apnea in conditions classified elsewhere |
| G47.39 | Other sleep apnea |
Most patients only ever interact with two of these, G47.33 for obstructive apnea and G47.30 for the unspecified version. The rest cover central apnea, altitude-related breathing problems, and several hypoventilation conditions that show up far less often in everyday practice. If your diagnosis involves the central form rather than the obstructive form, the relevant codes are G47.31 and G47.37, and I explain how that type differs in my article on central sleep apnea.
Why G47.30 and G47.33 are not interchangeable
This is the distinction that trips people up, and it is worth getting right. G47.30 is sleep apnea, unspecified. G47.33 is obstructive sleep apnea, specified. They sit one digit apart, but they tell very different stories to anyone reading the record.
G47.30 essentially means apnea was diagnosed but the type was not pinned down, or the documentation did not support a more specific code. It is the placeholder. G47.33 says the obstructive form was identified and supported by testing. For a tired clinician moving quickly, or for an electronic system that defaults to the broadest option, it can be tempting to reach for the unspecified code. The problem is that most insurers want to see the specific obstructive code before they will authorize CPAP therapy. An unspecified code on a claim that should have carried a specific one is one of the more common reasons a CPAP claim gets delayed or denied.
So if you are looking at your own paperwork and you see G47.30 rather than G47.33, and you know your sleep study confirmed obstructive apnea, that is a reasonable thing to ask your provider about. The fix is usually straightforward, but it tends to require the documentation to support the more specific code. None of this is something you have to manage alone, and your sleep clinic deals with it routinely, but understanding the difference puts you in a better position to ask the right question.
Why this code matters for getting CPAP covered
For most people with obstructive sleep apnea, the diagnosis code is not an abstract bookkeeping detail. It is the first link in the chain that ends with an insurer agreeing to pay for a machine, a mask, and the supplies you replace over the years. The code identifies the condition, and the clinical documentation behind it, particularly the results of your sleep study and your apnea hypopnea index, demonstrates that the condition meets the threshold for treatment.
This is the same reason the severity buried in your documentation matters even though the code does not capture it. Coverage rules often hinge on specific thresholds in the test data, and the diagnosis code by itself does not prove you cleared them. I go deeper into how diagnosis, documentation, and coverage fit together in my piece on CPAP insurance compliance, because the paperwork side of this therapy is its own learning curve, separate from the medical side.
What I want to leave you with here is just this. The code and the evidence behind it work as a pair. A correct code with thin documentation can still stumble, and strong documentation filed under the wrong code can stumble too. The system is looking for both to line up.
What supports the code: the documentation behind G47.33
A diagnosis code is only as solid as the record underneath it. For obstructive sleep apnea, that record generally rests on a sleep study, whether an overnight test in a lab or a validated home test, and the resulting measurement of how often your breathing was interrupted across the night. That figure, the apnea hypopnea index, is the number that defines the severity that your single diagnosis code does not.
When my own apnea was measured at an index of 51, that placed me well into the severe range, and that number, not the code, is what told the full story. The code said obstructive sleep apnea. The index said how badly. If you have not worked through what that measurement means or how the ranges break down, I lay it out plainly in my explanation of the apnea hypopnea index. The short version is that the code opens the file and the index fills it in.
Daytime sleepiness deserves a brief mention here too, because it is one of the most common reasons people end up tested in the first place. Excessive sleepiness is a symptom that supports an apnea diagnosis and is often noted in the record, but it is documented separately from the apnea itself rather than being part of the G47.33 code. The apnea code describes the breathing disorder. The sleepiness is one of its consequences, and it is recorded in its own right.
The exclusion notes, in plain language
ICD-10-CM attaches what it calls exclusion notes to many codes, and G47.33 has several. These are the coding system’s way of saying certain conditions should not be filed under this code even though they might sound related. You will not usually need to think about these as a patient, but they explain why a few apnea like conditions sit elsewhere.
Under G47.33, the system excludes apnea with no further specification, which is coded as R06.81, and it excludes Cheyne-Stokes breathing, coded as R06.3, a distinct breathing pattern rather than obstructive apnea. It also excludes pickwickian syndrome, coded as E66.2, which is tied to obesity related hypoventilation, and it excludes sleep apnea of the newborn, which carries its own code, P28.3, because infant apnea is a separate clinical situation. The point of all of this is precision. The coding system wants the obstructive apnea code reserved for obstructive apnea, with the look alike conditions kept in their own lanes.
How to verify any of these codes yourself
Because this is health information and codes update on a yearly cycle, I would rather hand you the primary source than ask you to take my word for it. The codes are maintained in the United States by the National Center for Health Statistics, part of the CDC, and you can read about the system and its updates on the official CDC ICD-10-CM page. The CDC also runs a free public code lookup tool at icd10cmtool.cdc.gov, where you can type in G47.33, or any other code in this article, and read the current official description straight from the source. If you ever want to confirm that a code on your own paperwork is still valid, that tool is the cleanest way to do it.
I mention this partly because the third party coding sites that dominate search results are usually accurate, but they are not the authority. The CDC and the official tabular list are. When the stakes involve your medical record or a claim, going to the source is a small habit worth keeping.
Common questions about the sleep apnea code
What is the ICD-10 code for sleep apnea? For the obstructive type, it is G47.33. For sleep apnea where the type has not been specified, it is G47.30. Obstructive is by far the most common, so G47.33 is the code most people are looking for.
Is there a different code for severe sleep apnea? No. G47.33 covers obstructive sleep apnea at every severity level. Mild, moderate, and severe all share the same code, and the severity is captured in the clinical documentation rather than in a separate code.
What is the code for unspecified sleep apnea? That is G47.30, sleep apnea, unspecified. It is used when the type was not determined or the documentation did not support a more specific code. If your testing confirmed the obstructive form, the more specific G47.33 is usually the appropriate code.
Does the code differ for children? No. G47.33 explicitly covers both adults and children. The official description even spells out adult and pediatric to make that clear.
Why does the code on my paperwork matter? Because it is the starting point for treatment coverage. Insurers generally want to see the specific obstructive code, supported by sleep study results, before authorizing CPAP therapy and supplies.
A patient’s bottom line
If you take one thing from this page, let it be that G47.33 is the obstructive sleep apnea code, that it does not change with severity, and that the documentation behind it is doing the heavy lifting. The code names the condition. Your sleep study and your apnea hypopnea index prove it and define how serious it is. Together they are what stand between a diagnosis and a treatment your insurer will actually pay for.
I find the coding side of sleep apnea oddly reassuring, in a way. After years of living with this condition, it is strangely grounding to know that the whole tangle of testing, treatment, and paperwork resolves down to a short string of characters that any system in the country can read the same way. It is not the interesting part of having sleep apnea. But when you are trying to get treated, it is one of the parts that has to be right.
⚠️ MEDICAL DISCLAIMER This blog provides general information only and is not a substitute for professional medical advice, diagnosis, or treatment. Sleep apnea is a serious condition, and CPAP equipment should be used under proper medical supervision. Always consult your doctor or sleep specialist before starting, stopping, or changing any therapy. I share personal experiences as a CPAP user, not as a medical professional. Individual results vary. For medical guidance, please consult a qualified clinician or the American Academy of Sleep Medicine (aasm.org).
