Hyperbaric oxygen therapy (HBOT) is covered by insurance, but only for a specific list of approved medical conditions. Medicare, most private insurers, and Medicaid all follow roughly the same list of 15 covered diagnoses. If your condition isn’t on that list, you’ll almost certainly pay out of pocket, with sessions running anywhere from $75 to $600 or more depending on the facility.
Conditions Insurance Will Cover
Medicare Part B covers HBOT for 15 conditions, and most private insurers use this same list as their baseline. The covered conditions fall into a few broad categories:
- Emergency and poisoning cases: carbon monoxide poisoning, cyanide poisoning, decompression illness (the bends), and gas embolism
- Severe infections: gas gangrene, necrotizing fasciitis (flesh-eating bacteria), and actinomycosis that hasn’t responded to antibiotics and surgery
- Traumatic injuries: crush injuries, severed limbs being reattached, and acute loss of blood flow to a limb when there’s risk of losing the limb or its function
- Radiation damage: bone death from radiation (osteoradionecrosis) and soft tissue damage from radiation, both as add-on treatment alongside conventional care
- Chronic bone infections: osteomyelitis that hasn’t responded to standard medical and surgical treatment
- Wound care: compromised skin grafts and diabetic wounds of the lower extremities (with specific qualifying criteria)
Emergency conditions like carbon monoxide poisoning and decompression sickness are treated urgently, so they don’t typically require prior authorization. Non-emergency uses, particularly diabetic wound care, almost always require approval before treatment begins.
Diabetic Wound Coverage Has Strict Requirements
Diabetic foot ulcers are one of the most common reasons people seek HBOT, and insurers apply the tightest qualifying criteria here. To get coverage, you must meet all three of these requirements: you have type 1 or type 2 diabetes with a lower extremity wound caused by the disease, the wound is classified as Wagner grade III or higher (meaning it extends at least to the tendon or bone level), and you’ve already tried standard wound care without measurable improvement for at least 30 consecutive days.
That 30-day threshold is non-negotiable for Medicare. Your medical records need to document the wound measurements over that period showing no signs of healing. Even then, HBOT is only covered as an add-on to continued standard wound care, not as a replacement for it.
Conditions Insurance Won’t Cover
Many of the conditions people associate with HBOT are explicitly excluded by insurers. Aetna, for example, labels HBOT as “experimental, investigational, or unproven” for autism spectrum disorders and stroke recovery, among a long list of other conditions. This classification means the insurer won’t pay regardless of what your doctor recommends.
Other commonly excluded uses include traumatic brain injury, PTSD, long COVID, Lyme disease, cerebral palsy, and anti-aging or general wellness applications. TRICARE, which covers military families, takes a similar stance: it covers proven rehabilitation services for TBI but doesn’t extend that to unproven standalone therapies like HBOT for brain injury. If a condition isn’t on the approved list, it’s effectively a cash-pay treatment.
How Prior Authorization Works
For non-emergency HBOT, your provider will need to submit a prior authorization request before you start treatment. This isn’t a separate documentation burden. It simply requires the medical records your doctor should already have: the diagnosis, wound measurements or imaging, documentation of failed conventional treatments, and the ordering physician’s information.
Your insurer or Medicare contractor will review the request and issue a decision letter. If the request is denied, the letter will explain what’s missing, and your provider can correct the deficiencies and resubmit. Getting denied on the first attempt doesn’t necessarily mean you won’t be covered. It often means the paperwork was incomplete or didn’t clearly demonstrate that you meet the qualifying criteria.
Session Limits and Treatment Duration
Insurance doesn’t give you unlimited sessions. The exact cap depends on your plan and state, but as a reference point, Maryland’s Medicaid program authorizes a maximum of 120 treatment units every 90 days, with up to 5 units per day. Most treatment courses for chronic conditions like diabetic wounds involve 20 to 40 sessions, each lasting about 90 minutes to two hours.
Your provider will typically request an initial block of sessions, then submit for additional authorization if more are needed based on how the wound or condition is responding. If your wound starts showing measurable healing, that supports continued approval. If it doesn’t respond after a reasonable course, coverage may not be extended.
What You’ll Pay Out of Pocket
For covered conditions, your out-of-pocket cost depends on your specific plan. With Medicare Part B, you’ll pay 20% of the approved amount after meeting your deductible, which applies whether you’re treated at a hospital outpatient department or a freestanding clinic. Private insurance copays and coinsurance vary by plan.
If your condition isn’t covered, you’re looking at the full cash price. Sessions in 2025 typically range from $150 to over $600, with hospital-based facilities generally charging more (around $300 per session in a hard-shell chamber) and some independent clinics offering rates as low as $75 to $129 per session, especially with bulk-session discounts. A full course of 30 to 40 sessions at cash rates can easily reach $5,000 to $20,000.
It’s worth noting that CMS corrected a payment error in early 2024 that had reduced hospital outpatient reimbursement for HBOT by over 40%. The correction was made retroactive to January 1, 2024, which stabilized access at hospital-based wound care centers that had been facing potential financial losses on every treatment.
How to Improve Your Chances of Approval
The single most important factor is having thorough documentation that your condition matches one of the approved indications. For diabetic wounds, that means detailed wound measurements taken over the full 30-day standard-care period, with records showing no improvement. For radiation injuries or chronic bone infections, you need documentation that conventional treatments were tried first.
Work with a wound care center or HBOT facility that regularly bills insurance, as they’ll know exactly what documentation your insurer expects. If your initial request is denied, ask your provider to review the denial letter carefully. Many denials result from missing paperwork rather than a true coverage dispute, and resubmission with complete records often resolves the issue.