Medicare requires ambulance suppliers to report two-character origin and destination modifiers on nearly all ambulance transportation claims. These modifiers identify where the patient was picked up and where the patient was transported, allowing Medicare to determine the transport route, verify medical necessity, and process claims accurately.
The letter R represents the patient’s Residence. It is not a standalone modifier and must always be combined with another origin or destination code to create a valid two-character ambulance modifier, such as RH, HR, RJ, JR, RN, or NR.
Modifier R is one of the most frequently used ambulance origin/destination codes because many medically necessary ambulance transports either begin at or end at the patient’s home.
Modifier
R
Modifier Name
Residence
Plain English Explanation
The letter R tells Medicare:
“The ambulance transport either started from or ended at the patient’s residence.”
A residence may include a private home, apartment, condominium, mobile home, or another location where the patient normally lives.
Purpose of Modifier R
Modifier R is used to:
- Identify the patient’s residence as the pickup or destination.
- Distinguish a residence from hospitals, Skilled Nursing Facilities, physician offices, dialysis centers, and other healthcare facilities.
- Report accurate ambulance origin and destination information.
- Support Medicare ambulance reimbursement.
- Comply with CMS ambulance billing requirements.
Understanding Modifier R
Ambulance origin and destination modifiers always consist of two letters.
- First Letter = Origin (Pickup Location)
- Second Letter = Destination (Drop-off Location)
Modifier R may appear in either position.
Common Modifier Combinations
| Modifier | Meaning |
|---|---|
| RH | Residence → Hospital |
| HR | Hospital → Residence |
| RJ | Residence → Freestanding ESRD Facility |
| JR | Freestanding ESRD Facility → Residence |
| RG | Residence → Hospital-Based ESRD Facility |
| GR | Hospital-Based ESRD Facility → Residence |
| RN | Residence → Skilled Nursing Facility |
| NR | Skilled Nursing Facility → Residence |
| RP | Residence → Physician’s Office |
| PR | Physician’s Office → Residence |
| RD | Residence → Diagnostic or Therapeutic Site |
| DR | Diagnostic or Therapeutic Site → Residence |
| RE | Residence → Residential/Domiciliary/Custodial Facility |
| ER | Residential/Domiciliary/Custodial Facility → Residence |
| RI | Residence → Transfer Site |
| IR | Transfer Site → Residence |
What Is Considered a Residence?
A residence is the location where the patient normally lives.
Examples include:
- Private home
- Apartment
- Condominium
- Townhouse
- Mobile home
- Farmhouse
- Temporary residence where the patient is currently living
- Relative’s home when it serves as the patient’s residence
Important: Assisted living facilities, custodial care facilities, Skilled Nursing Facilities, and hospitals are not considered a residence for ambulance modifier purposes and should be reported with their respective origin/destination codes.
When to Use Modifier R
Use Modifier R when:
- The patient is picked up from home.
- The patient is transported home after receiving medical care.
- The residence is the correct origin or destination.
- Ambulance transportation is medically necessary.
- Medicare coverage requirements are met.
When NOT to Use Modifier R
Do not use Modifier R when:
- The patient is picked up from or transported to a Skilled Nursing Facility (use N).
- The patient is picked up from or transported to an assisted living or custodial care facility (use E).
- The patient is picked up from or transported to a hospital (use H).
- Modifier R is reported alone.
- The location is a physician’s office, dialysis center, or other healthcare facility.
Medicare Rules
Under Medicare:
- Modifier R must always be paired with another valid origin/destination code.
- The first letter identifies the pickup location.
- The second letter identifies the destination.
- The patient’s residence must be accurately documented.
- Medical necessity for ambulance transportation must be established.
- Incorrect location coding may result in claim denial.
Although the patient’s home is a common origin or destination, ambulance transportation is covered only when other means of transportation would endanger the patient’s health and all Medicare coverage requirements are met.
Commercial Insurance Rules
Many commercial insurers follow Medicare’s ambulance origin and destination coding conventions.
However, individual payer requirements may differ regarding:
- Medical necessity.
- Prior authorization.
- Covered ambulance services.
- Documentation requirements.
- Reimbursement methodology.
Always verify payer-specific policies before billing.
Documentation Requirements
Documentation should include:
- Pickup address.
- Destination address.
- Confirmation that the residence is the patient’s normal place of living.
- Ambulance run report.
- Medical necessity documentation.
- Physician Certification Statement (PCS), when required.
- Date and time of transport.
- Mileage documentation.
- Crew signatures.
Real Billing Examples
Example 1 – Residence to Hospital
A patient with severe chest pain is transported by emergency ambulance from home to the emergency department.
Billing
- HCPCS A0427
- Modifier RH
- A0425 (Mileage)
Example 2 – Hospital to Residence
Following inpatient treatment, a bed-confined patient is discharged home by ambulance.
Billing
- HCPCS A0428
- Modifier HR
Example 3 – Residence to Dialysis Center
A patient with End-Stage Renal Disease is transported from home to a freestanding dialysis facility.
Billing
- HCPCS A0428
- Modifier RJ
Example 4 – Residence to Physician’s Office
A patient who cannot safely travel by wheelchair van requires ambulance transportation for an urgent physician appointment.
Billing
- HCPCS A0428
- Modifier RP
Example 5 – Incorrect Use
A provider reports:
A0428-R
This is incorrect because Modifier R cannot be billed by itself. Medicare requires a complete two-letter origin/destination modifier.
CMS-1500 Claim Example
| Field | Example |
| HCPCS | A0428 |
| Modifier | RH |
| Diagnosis Pointer | Appropriate ICD-10-CM diagnosis |
| Mileage | A0425 (if applicable) |
Common Denial Reasons
- Modifier R reported alone.
- Incorrect origin/destination modifier.
- Residence incorrectly identified.
- Missing ambulance run report.
- Medical necessity not documented.
- Missing mileage documentation.
- Invalid modifier combination.
How to Correct the Denial
- Verify the pickup and destination locations.
- Confirm that the residence is the patient’s normal place of living.
- Review the ambulance run report.
- Correct the origin/destination modifier.
- Submit supporting documentation.
- Resubmit or appeal when appropriate.
Coding Tips
- Never report Modifier R by itself.
- Verify that the residence is not actually an assisted living facility or Skilled Nursing Facility.
- Confirm the correct origin/destination sequence.
- Ensure documentation supports medical necessity.
- Maintain complete transport records.
Modifier R vs Modifier E
| Modifier | Description |
| R | Residence |
| E | Residential, Domiciliary, or Custodial Facility |
Modifier R vs Modifier N
| Modifier | Description |
| R | Residence |
| N | Skilled Nursing Facility |
Modifier R vs Modifier H
| Modifier | Description |
| R | Residence |
| H | Hospital |
Modifier R vs Modifier P
| Modifier | Description |
| R | Residence |
| P | Physician’s Office |
Frequently Asked Questions (FAQs)
Q1. Can Modifier R be billed by itself?
Answer: No. Modifier R must always be paired with another valid ambulance origin/destination code.
Q2. What does Modifier R represent?
Answer: The patient’s residence.
Q3. What does RH mean?
Answer: Residence → Hospital.
Q4. What does HR mean?
Answer: Hospital → Residence.
Q5. Is an assisted living facility considered a residence for Modifier R?
Answer: Generally, no. Assisted living, domiciliary, or custodial care facilities are typically reported using Modifier E, while Modifier R is used for the patient’s residence. Always verify the correct facility classification according to CMS guidance.
AR Caller Tips
When following up on ambulance claim denials involving Modifier R:
- Verify the patient’s pickup and destination addresses.
- Confirm that the residence is correctly classified.
- Review the ambulance run report.
- Verify medical necessity.
- Confirm mileage documentation.
- Ensure the correct two-letter modifier combination was billed.
- Record the payer representative’s name, reference number, and appeal instructions.
Interview Questions
Question 1
What does Modifier R represent?
Answer: The patient’s residence.
Question 2
Can Modifier R be reported alone?
Answer: No. Modifier R must always be combined with another valid ambulance origin/destination modifier.
Question 3
What is the difference between Modifier R and Modifier E?
Answer: Modifier R identifies the patient’s residence, while Modifier E identifies a residential, domiciliary, or custodial care facility.
Question 4
What modifier would be used for transport from home to a hospital?
Answer: RH (Residence → Hospital).
Practice Scenario
Scenario
A Medicare beneficiary experiences severe shortness of breath at home and requires emergency ambulance transport to the nearest hospital.
Question
Which modifier should be reported?
Answer
The correct modifier is RH, indicating Residence → Hospital.
Related Ambulance Modifiers
- D – Diagnostic or Therapeutic Site
- E – Residential, Domiciliary, or Custodial Facility
- G – Hospital-Based ESRD Facility
- H – Hospital
- I – Site of Transfer Between Modes of Ambulance Transport
- J – Freestanding ESRD Facility
- N – Skilled Nursing Facility
- P – Physician’s Office
- S – Scene of Accident or Acute Event
- X – Intermediate Stop at Physician’s Office (Destination Only)
Common Billing Mistakes
- Reporting Modifier R alone.
- Confusing a residence with an assisted living facility or SNF.
- Using an incorrect origin/destination sequence.
- Missing documentation supporting medical necessity.
- Incomplete ambulance run documentation.
- Incorrect mileage reporting.
Key Takeaways
- R represents the patient’s Residence.
- It is not a standalone modifier.
- It must always be combined with another valid ambulance origin/destination code.
- Correctly distinguishing a private residence from other facility types is essential for accurate ambulance billing.
- Complete documentation, medical necessity, and proper modifier selection help prevent Medicare claim denials.
References
- CMS Medicare Claims Processing Manual, Chapter 15 – Ambulance Services.
- CMS Ambulance Origin and Destination Codes Guidance.
- Medicare Administrative Contractor (MAC) Ambulance Billing Articles.
- HCPCS Level II Code Book.
- Medicare Benefit Policy Manual.
Conclusion
The R ambulance origin/destination code identifies transports involving a patient’s residence and is one of the most commonly used ambulance location codes in Medicare billing. Correct use requires pairing R with another valid origin/destination code, accurately documenting the patient’s pickup and destination locations, and meeting Medicare’s medical necessity requirements. Proper reporting promotes compliant billing, timely reimbursement, and fewer claim denials.
Educational Disclaimer
This article was prepared with the assistance of artificial intelligence (AI) for educational and informational purposes. It is based on publicly available CMS guidance, Medicare ambulance billing principles, and general medical coding practices. It is not an official publication of CMS or the American Medical Association (AMA). Always consult the latest CMS Medicare Claims Processing Manual, HCPCS Level II codebook, Medicare Administrative Contractor (MAC) guidance, and payer-specific billing policies before coding, billing, or submitting claims.