Place of Service Codes in Medical Billing: The Full List and the Ones Billers Mix Up

Place of service (POS) codes are the two-digit codes, maintained by CMS and used by every payer, that identify the setting where a service was performed. On a professional claim the code goes in box 24B of the CMS-1500 for every service line, and it decides which of two fee schedule rates the payer uses.

The field is small, but it changes the payment. For a group that treats in both its own center and the hospital, the same patient can need a different POS from one day to the next.

Where you see it

Place	What goes there
CMS-1500 box 24B	The two-digit POS for each service line
837P loop 2300, CLM05-1	The claim-level facility code; loop 2400, SV105 carries a line-level POS when it differs
Remittance advice	The POS column beside each date of service; our annotated remittance shows 11 for an office
Medicare Physician Fee Schedule	The facility and non-facility price columns that the POS selects between
Denials	CARC 5 (procedure inconsistent with the place of service), CARC 58 (inappropriate or invalid place of service), RARC M77 (missing, incomplete or invalid place of service)

The full list

The code set below is CMS’s current list. The rate column is Medicare’s, from the Claims Processing Manual, chapter 12, section 20.4.2; other payers usually follow it.

POS	Name	Medicare rate
01	Pharmacy	non-facility
02	Telehealth provided other than in patient’s home	facility
03	School	non-facility
04	Homeless shelter	non-facility
05	Indian Health Service free-standing facility	not listed in chapter 12
06	Indian Health Service provider-based facility	not listed in chapter 12
07	Tribal 638 free-standing facility	not listed in chapter 12
08	Tribal 638 provider-based facility	not listed in chapter 12
09	Prison or correctional facility	non-facility
10	Telehealth provided in patient’s home	non-facility
11	Office	non-facility
12	Home	non-facility
13	Assisted living facility	non-facility
14	Group home	non-facility
15	Mobile unit	non-facility
16	Temporary lodging	non-facility
17	Walk-in retail health clinic	non-facility
18	Place of employment or worksite	not listed in chapter 12
19	Off campus outpatient hospital	facility
20	Urgent care facility	non-facility
21	Inpatient hospital	facility
22	On campus outpatient hospital	facility
23	Emergency room, hospital	facility
24	Ambulatory surgical center	facility
25	Birthing center	non-facility
26	Military treatment facility	facility
27	Outreach site or street	non-facility
28 to 30	Unassigned
31	Skilled nursing facility	facility (Part A resident)
32	Nursing facility	non-facility (Part B resident)
33	Custodial care facility	non-facility
34	Hospice	facility (inpatient care)
35 to 40	Unassigned
41	Ambulance, land	facility
42	Ambulance, air or water	facility
43 to 48	Unassigned
49	Independent clinic	non-facility
50	Federally qualified health center	non-facility
51	Inpatient psychiatric facility	facility
52	Psychiatric facility, partial hospitalization	facility
53	Community mental health center	facility
54	Intermediate care facility, individuals with intellectual disabilities	non-facility
55	Residential substance abuse treatment facility	non-facility
56	Psychiatric residential treatment center	facility
57	Non-residential substance abuse treatment facility	non-facility
58	Non-residential opioid treatment facility	non-facility
59	Unassigned
60	Mass immunization center	non-facility
61	Comprehensive inpatient rehabilitation facility	facility
62	Comprehensive outpatient rehabilitation facility	non-facility
63 to 64	Unassigned
65	End-stage renal disease treatment facility	non-facility
66	Programs of All-Inclusive Care for the Elderly (PACE) center	not listed in chapter 12
67 to 70	Unassigned
71	Public health clinic	non-facility
72	Rural health clinic	non-facility
73 to 80	Unassigned
81	Independent laboratory	non-facility
82 to 98	Unassigned
99	Other place of service	non-facility

The ones billers mix up

Pair	The difference
02 vs 10	Both telehealth. 02 is anywhere but the patient’s home and pays the facility rate; 10 is the patient’s home and pays the non-facility rate
11 vs 22	Who owns the room. 11 is the practice’s own office or freestanding center; 22 is a hospital department on the main campus, where the hospital bills the facility side
19 vs 22	On or off the hospital campus. 19 is a hospital-owned department off campus, created in 2016 so Medicare could pay it differently; both are the facility rate for the physician
21 vs 22	The patient’s status, not the building. An admitted inpatient is 21; an outpatient, including a patient under observation, is 22
22 vs 23	The emergency department is 23 even though it is on campus and outpatient
22 vs 24	An ambulatory surgical center is a freestanding, separately certified facility, not a hospital department

Medicare adds one rule that overrides the face-to-face location: for a service to a patient who is a hospital inpatient (21) or a hospital outpatient (19 or 22), the facility rate is paid regardless of where the physician actually saw the patient.

How POS sets payment

The Medicare fee schedule carries two practice expense values for most codes, and the POS picks one. The non-facility rate includes the practice’s own overhead: the room, the staff, the equipment. The facility rate assumes a hospital or ASC is bearing those costs and billing its own claim, so it pays the physician less. The mechanics, including why the professional component is priced the same in both settings, are in our article on facility vs non-facility rates.

For radiation oncology the two settings are a freestanding center (POS 11), where the practice bills the global code, and a hospital outpatient department (POS 22), where the physician bills the professional component with modifier 26 and the hospital bills the technical component on its own claim. Our POS 22 article goes through that case in detail.

A worked example

Two services, 2026 national Medicare amounts before geographic adjustment, from the October 2026 relative value file at the non-APM conversion factor of 33.4009:

Service	POS 11 (office)	POS 22 (hospital outpatient)
99213, established patient visit	2.85 RVU, 95.19	1.72 RVU, 57.45
77300, basic dosimetry calculation	global, 2.01 RVU, 67.14	77300-26, 0.98 RVU, 32.73 (the technical component, 1.03 RVU, is the hospital’s)

The visit code is the same service in both settings; the 37.74 difference is the practice expense Medicare assumes the hospital is paying for. For 77300 the physician’s share in the hospital is the professional component only; billing the global code with POS 22 bills for equipment the practice does not own.

What to do

• Set the POS from where the patient was, per visit, not from a practice default. A group with a freestanding center and a hospital contract needs both settings live in the system and selected from the schedule.
• Match the modifier to the POS. POS 19, 21 or 22 with a code that has a technical component means modifier 26 on the physician claim. The Iridium Suite claim scrubber checks the place of service on each line against the payer’s billing rules before the claim is sent, so a POS and modifier mismatch can be fixed first.
• Watch patient status at the hospital. Observation is outpatient (22); the switch to inpatient (21) happens on the admission order, not on arrival.
• Recognize the denials. CARC 5 and CARC 58, often with RARC M77, are coding corrections: fix the POS or the code and resubmit. They are not appeals.
• Re-check hospital departments once a year. One that moved off campus changes from 22 to 19 with nothing else about the service changing.

Related terms

• Place of service 22: on campus outpatient hospital
• Facility vs non-facility rates
• Modifiers 26 and TC
• CMS-1500 box by box
• Claim adjustment group and reason codes

Further reading: CMS Place of Service Code Set; CMS place of service codes overview; Medicare Claims Processing Manual, chapter 12, section 20.4.2, site of service payment differential (PDF); X12 claim adjustment reason codes.