Oxygen 36-Month Cap Refresher

What this page is for

Use this when handling Medicare oxygen rentals approaching the cap, switching providers, determining billing responsibility, or resolving questions on the 36-month and 60-month cycles.


1. What the 36-Month Cap Means

Medicare pays 36 monthly rental payments for oxygen equipment.

After month 36:

  • The supplier is responsible for furnishing and maintaining the oxygen equipment at no cost to the beneficiary.
  • Monthly rental billing stops.
  • Medicare continues to pay for oxygen contents (E0443, E0441, E0442) if medically necessary.
  • The beneficiary remains in a 60-month capped rental cycle.

2. Supplier Responsibilities After Month 36

After the cap is reached, the supplier must:

  • Maintain and service the concentrator
  • Replace broken equipment (unless misuse)
  • Provide backup tanks if medically needed
  • Respond to service calls
  • Not bill Medicare for rental or maintenance unless in a rare M&S case

In short: Medicare stops paying, but you don’t stop working.


3. What You Can Still Bill After Month 36

Portable oxygen contents
Liquid contents
Backup tanks (if justified)
Accessories only in limited cases where not included in the original rental


4. What You Cannot Bill

❌ Rental items (E1390, E0431, E0434, etc.)
❌ Concentrator replacements (unless 60+ month cycle reset)
❌ Routine maintenance
❌ Patient pickup / delivery fees
❌ Restarts of capped rental


5. When the 60-Month Cycle Resets

A new 60-month cycle begins only when:

  1. The full 60 months have passed, and
  2. The patient still qualifies medically, and
  3. A new initial claim is submitted

This is the only time rental billing may start over.


6. Patient Transfers

A. Transfer BEFORE Month 36

  • The new supplier takes over remaining rental months.
  • Rental continues from whatever month the previous supplier left off.
  • Requires:
    • SWO
    • Qualifying documentation
    • Proof of continued need

B. Transfer AFTER Month 36

  • The original supplier remains responsible for furnishing equipment through month 60.
  • A new supplier cannot bill rental.
  • A new supplier can accept the patient, but must do so without rental payment.
  • Documentation proving release from responsibility is extremely rare.

Bottom line:
If the patient is capped, the responsibility follows the equipment, not the supplier.


7. Maintenance & Servicing (M&S)

M&S billing is rare. It applies only when:

  • The equipment is beyond useful life after the 5-year cycle, and
  • A home visit is medically required

In almost all other situations, M&S billing is not allowed.


8. Documentation Needed

  • SWO
  • Medical necessity confirming ongoing need
  • Proof of patient use
  • Prior rental history (HETS lookup or internal records)
  • Contents necessity (if billing contents)

Lack of ongoing need documentation can cause contents denial.


9. Quick Reference Table

ScenarioBillable?Notes
Months 1–36✔ RentalStandard rental cycle
Month 36+❌ RentalSupplier responsibility starts
Portable contentsIf medically necessary
Transfer <36 monthsContinue remaining rental months
Transfer >36 months❌ RentalNew supplier inherits responsibility
Replacement <60 monthsNo reset
Replacement 60+ monthsNew cycle begins

10. Staff TL;DR

  • 36 months = no more rental billing.
  • Supplier must still service equipment until month 60.
  • Contents may still be billable.
  • Transfers after month 36 = you take responsibility, not rental revenue.
  • New rental only after the full 60-month cycle ends.