Place of Service Codes on NEMT Claims: Which Code Your Payer Wants in Box 24B

What a place of service code is

Every line on a professional claim carries a two-digit place of service code. The NUCC’s claim form manual (version 13.0, July 2025) says the code “identifies the location where the service was rendered” and tells you to take it from the CMS list. CMS keeps that list for all payers. Its database was last updated May 2, 2024, and its page tells you to “Check with individual payers (e.g., Medicare, Medicaid, other private insurance) for reimbursement policies regarding these codes.”

That last line matters for NEMT. The list was built for places where care happens, such as offices, hospitals, and homes. A ride happens in a vehicle, and the only transport vehicles on the list are ambulances. So each Medicaid program decides which code a van, sedan, taxi, or rideshare trip should carry.

These are the codes a transportation company runs into:

Code	CMS name	What it means for a NEMT claim
99	Other place of service	“Other place of service not identified above.” The code most programs name for rides that are not ambulance trips.
41	Ambulance, land	“A land vehicle specifically designed, equipped and staffed for lifesaving and transporting the sick or injured”
42	Ambulance, air or water	The air or water version of 41
21	Inpatient hospital	Medi-Cal uses it when a hospital inpatient rides out and back
09	Prison or correctional facility	Texas lists it for paper Medical Transportation Program claims
12, 31, 32, 65	Home, skilled nursing facility, nursing facility, end-stage renal disease treatment facility	Common pickups and destinations. They describe places of care, so a trip to one still takes the code your payer names for rides.

Which code each program wants

The code comes from your payer’s billing rules, not from the national list. These programs name one:

Program	Code for NEMT	Where it is written
New York Medicaid	99 for non-emergency trips. 41 (land) or 42 (water or air) for emergency trips.	Transportation billing guidelines, version 2026-02 (August 5, 2026), field 20 of its claim form and CLM05-1 of the 837P
North Carolina Medicaid managed care	99 for taxi, bus, mini-bus, van, car, and rideshare trips. 41 or 42 for ambulances.	NEMT managed care policy (amended January 1, 2025), on the encounter for each trip leg
Oregon Health Plan, fee-for-service	99 for transportation providers that are not ambulances. 41 and 42 for ambulances.	OHA Medical Transportation Services Provider Guide (December 22, 2025)
Nevada Medicaid, ride encounters	99	NET 837P encounter companion guide (August 4, 2026), CLM05-1
North Dakota Medicaid Expansion (BCBSND)	Providers can use 99	BCBSND’s NEMT provider page (September 2026), which also suggests diagnosis Z59.5
Texas Medical Transportation Program	09 on paper claims. 99 in TexMedConnect.	MTP handbook (September 2026)
Medi-Cal fee-for-service	21 when a hospital inpatient rides to an appointment and back	Ground medical transportation manual (page updated August 2020)

If you drive for a broker, it may take trips on its own invoice rather than a claim form. Ask what it wants, because in managed care the code you give it can travel on. North Carolina’s policy has each trip leg reported to the state as an encounter that names the broker as billing provider, the transportation company as rendering provider, and a place of service. Your state’s page, such as Texas or New York, lists the rest of its billing rules.

Why a wrong code gets a trip denied

Payers check the place of service against the procedure code and their own rules. When it fails, the remittance usually says so in one of three codes, all worded by X12:

Code	Type	X12 wording
5	Reason code	The procedure code/type of bill is inconsistent with the place of service.
58	Reason code	Treatment was deemed by the payer to have been rendered in an inappropriate or invalid place of service.
M77	Remark code	Missing/incomplete/invalid/inappropriate place of service.

Read these with the group code in front of them. For the rest of the denial codes you will see, see claim adjustment reason codes and remittance advice remark codes.

Some payers also print the code in a different form. Texas’s claims manual (September 2026) turns two-digit codes into one-digit codes on its Remittance and Status report. Codes 99, 41, and 42 all print as 9, “other location,” so a 9 in the place of service column on a Texas NEMT line is normal.

Place of service is not the pickup or the destination

A NEMT claim has to show where the rider was picked up and dropped off, but that is a separate field. Most programs use the two-letter origin and destination modifiers on each procedure code for it.

• Oregon asks for the pickup and destination as one two-digit modifier: the first letter is the pickup point and the second is the drop-off. The place of service stays 99.
• Nevada requires origin and destination modifiers on each procedure code in its ride encounters, alongside place of service 99. Pharmacy trips take initial and return trip modifiers instead.
• Medi-Cal is the one program above where the place of service changes with the rider: a hospital inpatient’s trip out and back takes 21, with the hospital’s address and NPI in boxes 32 and 32A.

Where the code goes on paper and electronic claims

Claim	Where the code goes	Notes
CMS-1500 paper claim	Box 24B, on every service line	Two digits in the unshaded area
837P electronic claim	CLM05-1 in loop 2300 for the claim, and SV105 in loop 2400 for a service line	The NUCC map (version 3.3) calls CLM05-1 the Facility Code Value
New York’s paper claim form	Field 20	New York paper transportation claims go on its own eMedNY-000201 form (Form A), not the CMS-1500

See the box-by-box CMS-1500 guide for NEMT and the 837P for the fields around it.

How to set the right code for each payer

1. Look it up in your state’s manual. Search the transportation billing guide for “place of service.” Your state guide on this site links the manual.
2. Ask each broker and health plan. Each can set its own rule. Write the answer down with the date and the person who told you.
3. Set one default per payer. If your billing setup can store a place of service for each payer, use it, so you do not type the code trip by trip.
4. Flag the exceptions. Texas paper claims differ from TexMedConnect claims, and Medi-Cal hospital inpatient trips take 21.
5. Keep pickup and drop-off in the modifiers. Changing the place of service to match the pickup is only right where your payer says so.
6. Watch your remittances. Reason code 5 or 58, or remark M77, means the code needs fixing. Correct it and resend within the filing limit. See NEMT claim denials and corrected NEMT claims.