Summary: The Centers for Medicare & Medicaid Services modified its Hyperbaric Oxygen Therapy coverage policy, effective May 15, 2026. Here's what billing teams need to do.
CMS hyperbaric oxygen therapy coverage policy changes carry real financial weight for wound care centers, hospital outpatient departments, and any practice billing HBO treatment to Medicare patients. This modification updates the existing CMS policy governing when hyperbaric oxygen therapy is covered, what conditions qualify, and what gets denied. The policy does not carry a numbered policy code in the standard NCD or LCD format — reference it directly at the CMS source. No specific CPT or HCPCS codes are listed in the available policy data, so check your current charge capture against the CMS source document before May 15, 2026.
Quick-Reference Table
| Field | Detail |
|---|---|
| Payer | CMS (Centers for Medicare & Medicaid Services) |
| Policy | Hyperbaric Oxygen Therapy |
| Policy Code | N/A |
| Change Type | Modified |
| Effective Date | May 15, 2026 |
| Impact Level | High |
| Specialties Affected | Wound care, hyperbaric medicine, hospital outpatient departments, vascular surgery, plastic surgery, podiatry |
| Key Action | Review documentation requirements and medical necessity criteria against the updated policy before May 15, 2026 |
CMS Hyperbaric Oxygen Therapy Coverage Criteria and Medical Necessity Requirements 2026
Hyperbaric oxygen therapy — pressurized oxygen delivered in a sealed chamber — has one of the tighter medical necessity frameworks under Medicare. CMS has long drawn a hard line between covered and non-covered indications. This modification doesn't loosen that line. If anything, expect it to sharpen it.
CMS covers hyperbaric oxygen therapy only when the treating physician documents that the condition is on the approved covered indications list and that standard wound care has failed or is insufficient. Medical necessity is not assumed. It must be established in the clinical record before treatment begins, not reconstructed after a claim denial.
The core covered indications under CMS hyperbaric oxygen therapy policy have historically included diabetic wounds of the lower extremities (Grade III or higher under Wagner classification), chronic refractory osteomyelitis, osteoradionecrosis, soft tissue radionecrosis, compromised skin grafts and flaps, acute carbon monoxide intoxication, gas gangrene, and a defined list of other serious conditions. Prior authorization is not universally required under Medicare fee-for-service for hyperbaric oxygen therapy, but documentation supporting medical necessity must be in the chart before the claim goes out.
Your Medicare Administrative Contractor may impose additional local coverage determination requirements on top of the national policy. Check with your MAC — Novitas, NGS, CGS, and others have published LCDs that layer additional criteria onto the CMS framework. A claim that passes national policy review can still get denied at the MAC level.
This is a high-exposure policy for wound care centers. The average course of hyperbaric oxygen therapy runs 20 to 40 sessions. A denial on medical necessity grounds — especially a post-payment audit denial — means recovering that reimbursement is an uphill fight.
CMS Hyperbaric Oxygen Therapy Exclusions and Non-Covered Indications
CMS does not cover hyperbaric oxygen therapy for conditions it considers unproven or not supported by clinical evidence. This is where most claim denials originate — billing HBO for an indication that sounds reasonable clinically but isn't on the covered list.
Historically non-covered conditions under CMS include: stroke, traumatic brain injury, cerebral palsy, multiple sclerosis, Lyme disease, autism spectrum disorder, migraine, Alzheimer's disease, and wound healing not meeting the clinical severity thresholds. These are the conditions where patients and providers often push hardest for HBO access, and where CMS has consistently held the line.
Billing HBO for a non-covered indication is not just a claim denial risk. If you're billing Medicare for services you know or should know aren't covered, you're in compliance territory that goes beyond revenue cycle. Talk to your compliance officer before submitting claims for any indication that isn't clearly on the covered list.
The real issue here is that some conditions sit in a gray zone — documented in the literature but not formally approved by CMS. Billing teams aren't in a position to make that call. That determination needs to come from your medical director and compliance officer, not from charge capture staff.
Coverage Indications at a Glance
The policy data provided does not include an indication-by-indication breakdown with specific coverage determinations. The table below reflects the historically established CMS framework for hyperbaric oxygen therapy coverage. Verify each row against the updated May 15, 2026 policy document at the CMS source before relying on this for billing decisions.
| Indication | Status | Notes |
|---|---|---|
| Diabetic wounds of lower extremities (Wagner Grade III or higher) | Covered | Must document failure of standard wound care; physician must assess patient every 30 days |
| Chronic refractory osteomyelitis | Covered | Must document failure of standard medical/surgical treatment |
| Osteoradionecrosis | Covered | Must be a consequence of radiation therapy |
| Soft tissue radionecrosis | Covered | Radiation-induced; must be documented |
| Compromised skin grafts and flaps | Covered | Attending physician must determine HBO is necessary |
| Acute carbon monoxide intoxication | Covered | Emergency indication |
| Gas gangrene (clostridial myonecrosis) | Covered | Emergency indication |
| Crush injuries and suturing of severed limbs | Covered | Acute traumatic indication |
| Decompression illness | Covered | Diving-related emergency |
| Air or gas embolism | Covered | Emergency indication |
| Stroke | Not Covered | CMS considers evidence insufficient |
| Traumatic brain injury | Not Covered | CMS considers evidence insufficient |
| Cerebral palsy | Not Covered | CMS considers evidence insufficient |
| Multiple sclerosis | Not Covered | CMS considers evidence insufficient |
| Autism spectrum disorder | Not Covered | CMS considers evidence insufficient |
| Lyme disease | Not Covered | CMS considers evidence insufficient |
| Alzheimer's disease | Not Covered | CMS considers evidence insufficient |
| Migraine | Not Covered | CMS considers evidence insufficient |
| Wound healing not meeting clinical severity thresholds | Not Covered | Indication must meet Wagner Grade III or higher for diabetic wounds |
CMS Hyperbaric Oxygen Therapy Billing Guidelines and Action Items 2026
The effective date is May 15, 2026. That gives your billing and clinical teams a defined window to get aligned. Here's what to do before then.
| # | Action Item |
|---|---|
| 1 | Pull the updated CMS policy document now. Go directly to the source at app.payerpolicy.org/p/cms/12-v4. Read the modification against your current billing protocols. Don't rely on what you knew before this change — confirm what shifted. |
| 2 | Audit your hyperbaric oxygen therapy billing for the last 90 days. Look for claims where the documented indication is anything other than a clear covered condition. If those claims are still in the adjudication cycle, your compliance officer needs to know now. |
| 3 | Check your MAC's local coverage determination. Your MAC may have an LCD that adds criteria on top of the CMS national policy. Confirm whether your MAC has updated its LCD in response to this modification. If it hasn't yet, expect it to follow. |
| 4 | Verify your 30-day physician assessment documentation. For diabetic lower extremity wounds, CMS requires a treating physician to assess the patient every 30 days and document that the wound is responding to treatment. This is one of the most common documentation failures in hyperbaric oxygen therapy billing. Audit your current patient population now. |
| 5 | Update your charge capture workflow before May 15, 2026. Your charge capture staff should not be selecting HBO procedure codes without a documented covered indication in the chart. Build a hard check into your workflow — if the indication isn't on the covered list, the claim doesn't go out without compliance review. |
| 6 | Brief your wound care and hyperbaric medicine physicians. Billing guidelines don't fix claim denials if the clinical documentation doesn't support them. Your physicians need to know what CMS requires in the medical record — not just that the therapy is indicated clinically, but that the chart demonstrates medical necessity in CMS's specific terms. |
| 7 | If your volume is significant, loop in your compliance officer before May 15. Hyperbaric oxygen therapy is an area CMS has audited aggressively. High-volume HBO programs are a known target for Recovery Audit Contractor (RAC) reviews. If you're running 20+ treatment courses a month, your compliance officer should review your documentation protocols now — not after the first audit letter arrives. |
| Previous Version | Current Version |
|---|---|
| Coverage is considered experimental and investigational for all indications | Coverage is considered medically necessary when specific criteria are met |
| Prior authorization is not required | Prior authorization is required for initial treatment |
| Documentation must include clinical history | Documentation must include clinical history |
| Re-review every 24 months | Re-review every 12 months with updated clinical documentation |
CPT, HCPCS, and ICD-10 Codes for Hyperbaric Oxygen Therapy Under CMS Policy
The policy data provided does not list specific CPT, HCPCS, or ICD-10 codes. Do not bill based on codes inferred from this post alone.
Pull the complete code list directly from the CMS policy document and your MAC's LCD. Cross-reference against your current charge master before May 15, 2026.
For reference, hyperbaric oxygen therapy billing has historically involved HCPCS codes in the A and G code ranges for facility billing and specific CPT codes for the physician supervision component. The exact codes — and whether they're covered, non-covered, or require specific modifier use — depend on the policy language in the updated document.
Your billing team should confirm:
- Which HCPCS codes your facility uses for HBO sessions
- Whether modifier use requirements changed in this modification
- How your MAC's fee schedule treats the updated policy for reimbursement calculations
- Whether any codes previously covered have shifted to non-covered status, or vice versa
Do not guess at codes. Get the current list from CMS directly and reconcile it with your charge master.
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