Place of Service Codes in Medical Billing: Quick Guide

A small POS code can make a big difference in medical billing.

The place of service (POS) code tells the payer where a healthcare service was provided, such as an office, hospital, home, or telehealth setting. CMS maintains the standard POS code set for professional claims. For billing teams, the key is choosing the code that accurately matches the actual setting of care and supports proper claim processing and payment.

Not sure which place of service code fits your claims? We can help review your billing workflow, verify POS coding, identify common errors, and support claim follow-up so your team can bill with greater accuracy and fewer avoidable issues. 

What Are Place of Service Codes in Medical Billing?

Place of Service codes are two-digit codes reported on professional healthcare claims to identify the entity or setting where services were rendered.

CMS notes that the POS code set is used as the national standard for describing sites of service on professional claims.

The POS code is not a CPT code, diagnosis code, or modifier. It answers a different question:

Where did the service take place?

That location needs to make sense with the rest of the claim.

Why Do POS Codes Matter in Medical Billing?

POS coding may look like a small field on a claim, but it can have a broader impact on how a professional service is processed.

Billing Area	Why POS Matters
Claim processing	Identifies the setting where the service occurred
Payment methodology	May determine whether facility or non-facility payment logic applies for certain services
Telehealth	Distinguishes whether the patient was at home or elsewhere
Facility billing	Helps distinguish hospital, SNF, ASC, and other settings
Claim accuracy	Keeps the reported setting consistent with the actual encounter
Audits and reviews	Provides evidence about where the service was performed
Payer rules	Some payers have specific reimbursement policies tied to POS

Under the Medicare Physician Fee Schedule, some services have separate facility and non-facility rates. CMS states that the POS code is used to identify the setting and can determine which payment rate applies.

That does not mean every POS code automatically changes reimbursement. The effect depends on the service, payment system, and payer rules.

CMS also specifically instructs providers to check individual payer policies regarding POS reimbursement.

What Are the Most Common Place of Service Codes?

Providers do not necessarily need to memorize the entire POS code set, but billing teams should be comfortable with the codes they encounter regularly.

These descriptions are based on CMS’s current POS code set for professional claims. CMS maintains additional codes for settings such as schools, homeless shelters, assisted living facilities, Indian Health Service facilities, community mental health centers, inpatient psychiatric facilities, hospice, ambulance services, and rehabilitation facilities.

POS 02 vs. POS 10: What’s the Difference?

POS 02 and POS 10 are both telehealth codes, but they are not interchangeable.

The difference is the patient’s location.

CMS established POS 10 to distinguish telehealth provided when the patient is at home from telehealth provided at another location.

Example

A physician conducts a video follow-up with a patient who is sitting in their living room.

POS 10 would identify the patient’s home as the telehealth location, subject to the payer’s applicable billing requirements.

Now consider a patient who connects to the same type of virtual visit while at another location, such as a healthcare facility.

The setting is different, so POS 02 may apply when permitted by the payer.

The key question is not:

“Was this a video visit?”

It is:

“Where was the patient when the telehealth service was provided?”

POS 11 vs. POS 19 vs. POS 22

These three codes are especially important for practices connected to hospitals.

POS	Setting	Key Difference
11	Office	Routine ambulatory care in an office setting
19	Off-Campus Outpatient Hospital	Hospital outpatient department located off the main campus
22	On-Campus Outpatient Hospital	Hospital outpatient department on the hospital’s main campus

CMS defines POS 19 for an off-campus outpatient hospital setting and POS 22 for an on-campus outpatient hospital setting. POS 11 is used for an office setting that meets CMS’s definition.

Why the distinction matters

Imagine a physician sees patients in three different locations:

Private physician office → POS 11

Hospital outpatient department on the hospital campus → POS 22

Hospital outpatient department at a separate off-campus location → POS 19

The fact that the same physician performed the service does not mean the same POS code should be used for every encounter.

The actual setting of the service matters.

POS 21 vs. POS 22 vs. POS 23

Another common source of confusion is hospital-based care.

Being inside a hospital does not automatically mean the claim should use POS 21.

POS	Setting	When It Applies
21	Inpatient Hospital	Patient is receiving inpatient hospital care
22	On-Campus Outpatient Hospital	Patient receives outpatient services on the hospital campus
23	Emergency Room – Hospital	Service is provided in the hospital emergency department

The difference is based on the type of setting and encounter, not simply the physical building. CMS maintains separate definitions for inpatient hospital, outpatient hospital, and emergency room services.

Simple example

A patient is admitted to the hospital and receives a professional service as an inpatient.

POS 21

The patient comes to the hospital for a scheduled outpatient service.

POS 22

The patient receives care in the hospital emergency department.

POS 23

That distinction should be reflected accurately on the professional claim.

POS 31 vs. POS 32 vs. POS 33

Nursing-related settings can also create confusion because the names sound similar.

POS	Place of Service	Basic Distinction
31	Skilled Nursing Facility	Inpatient skilled nursing/rehabilitative setting
32	Nursing Facility	Nursing facility setting
33	Custodial Care Facility	Custodial care setting

The correct code depends on the actual facility and the services being provided. CMS maintains separate POS definitions for these settings.

A biller should therefore avoid choosing a code based only on the word “nursing” appearing in the facility’s name.

How Do You Choose the Correct POS Code?

Choosing a POS code becomes much easier when the billing team follows the same process for every claim.

Step 1: Identify Where the Service Actually Occurred

Start with the actual location of the encounter.

Do not automatically use the provider’s primary office location.

A physician may have one NPI and practice at several locations, each with a different POS.

Step 2: Determine Whether the Service Was In-Person or Telehealth

For telehealth, determine where the patient was located.

If the patient was at home, POS 10 may apply.

If the patient was somewhere other than home, POS 02 may apply, depending on the payer’s requirements.

Step 3: Identify the Facility Type

Ask:

• Was it a private office?
• A hospital?
• An outpatient hospital department?
• An ASC?
• A patient’s home?
• An SNF?
• A nursing facility?
• An independent clinic?
• Another specialized setting?

Step 4: Match the Setting to the CMS Definition

Do not rely solely on what the location is called internally.

Compare the actual setting with the CMS POS definition.

Step 5: Check the Payer’s Policy

CMS specifically advises providers to check individual payer policies regarding POS codes and reimbursement.

This matters because Medicare, Medicaid programs, and commercial insurers can have different reimbursement rules.

Step 6: Check the Rest of the Claim

The POS should make sense alongside:

• CPT/HCPCS code
• Modifier
• Diagnosis
• Provider information
• Facility information
• Patient location
• Payer requirements

A POS code should tell the same story as the rest of the claim.

Where Is the POS Code Reported on a Medical Claim?

POS codes are used on professional claims to identify where the service was rendered.

For electronic professional claims, the POS code is part of the standard claim data used to describe the site of service. CMS identifies the POS code set as the national standard for professional claims.

The code is also associated with the service line rather than being treated as a diagnosis or procedure code.

That distinction matters because changing the POS does not change the underlying CPT code.

For example:

CPT = What service was performed?
ICD-10-CM = Why was it performed?
POS = Where was it performed?

These elements work together to describe the claim.

Does the Place of Service Code Affect Reimbursement?

It can.

Under the Medicare Physician Fee Schedule, certain professional services have separate facility and non-facility payment rates. CMS explains that POS is used to identify the setting and can determine which rate applies.

Generally, the difference reflects where the resources associated with the professional service are incurred.

For example, Medicare’s Physician Fee Schedule generally pays most office-based physician services using a rate that includes the resources required to furnish the service in the office. Facility-setting rates generally reflect that the facility is supplying certain resources separately.

Why this matters for billing teams

An incorrect POS can therefore create more than a data-quality issue.

Depending on the service and payer, it can contribute to:

• Incorrect payment
• Claim edits
• Reimbursement discrepancies
• Manual review
• Denials or rework

CMS has specifically identified incorrect facility-versus-non-facility reimbursement as a claim-review issue.

However, billing teams should not assume that changing a POS automatically changes payment. The applicable service, payer, fee schedule, and reimbursement policy all matter.

What Are Common POS Coding Mistakes?

1. Using POS 11 for Every Office-Like Encounter

A provider may routinely see patients in an office, but that does not mean every ambulatory location is POS 11.

Hospital outpatient departments may require POS 19 or 22 depending on their location and classification.

2. Confusing POS 02 and POS 10

Both represent telehealth, but the patient’s location is different.

Patient at home → POS 10

Patient somewhere other than home → POS 02

Subject to applicable payer requirements.

3. Using POS 21 Because the Service Happened in a Hospital

POS 21 represents an inpatient hospital setting.

An outpatient hospital encounter may instead require POS 19 or 22.

4. Confusing POS 19 and POS 22

The distinction is whether the outpatient hospital department is off campus or on campus.

5. Choosing POS 31 or 32 Based Only on the Facility Name

SNF and nursing facility are not interchangeable POS definitions.

6. Using POS 99 as a Default

POS 99 means Other Place of Service, a setting not identified by another POS code.

It should not become a convenient substitute for researching an unclear location.

7. Ignoring Payer-Specific Rules

A POS code can be technically valid under the CMS code set while still being subject to additional payer reimbursement requirements.

How Can an Incorrect POS Code Affect a Claim?

Think about the claim as a story.

The CPT code says what happened.

The diagnosis code helps explain why it happened.

The POS code says where it happened.

If those pieces do not agree, the payer may have questions.

For example:

Documentation: Patient seen in hospital outpatient department

Claim POS: Office

The CPT code might be completely correct, but the reported setting does not match the encounter.

That mismatch can lead to claim rework, payment discrepancies, or additional review depending on the payer and service.

A Better Billing Workflow

Actual service location

↓

Identify the correct POS category

↓

Verify CMS definition

↓

Check payer policy

↓

Compare POS with CPT, modifiers, and documentation

↓

Submit claim

This simple workflow can prevent POS selection from becoming an after-the-fact correction.

Place of Service Codes for Telehealth, Home, and Facility-Based Care

For quick reference:

Scenario	Potential POS
Telehealth, patient at home	10
Telehealth, patient somewhere other than home	02
In-person service in patient’s home	12
Routine office visit	11
On-campus hospital outpatient service	22
Off-campus hospital outpatient service	19
Inpatient hospital service	21
Hospital emergency department service	23
Ambulatory surgical center	24
Skilled nursing facility	31
Nursing facility	32

These are CMS-defined settings, but the final claim should always be checked against the applicable payer’s billing requirements.

Full Place of Service Code Reference

CMS’s POS code set contains many more settings than the codes most physician practices use every day.

CMS’s current code-set page notes that some numeric ranges are unassigned and provides the formal descriptions for the active codes.

For production billing, teams should use the current CMS code set and applicable payer guidance rather than relying on a static online list.

Are There 2026 Changes to Place of Service Codes?

CMS’s main Place of Service page was updated in February 2026, and the POS code-set page was also updated in February 2026.

However, the code-set database displayed by CMS is identified as updated May 2, 2024. CMS continues to maintain the page and directs billing questions to the applicable Medicare Administrative Contractor.

The practical takeaway for providers is not to assume that a POS code list found online is permanently current.

Before submitting claims, billing teams should verify:

• Current CMS POS definitions
• Medicare MAC guidance
• Commercial payer policies
• Medicaid requirements where applicable
• Any payer-specific reimbursement instructions

This is especially important when a practice adds a new location, begins telehealth, moves into a hospital-owned facility, or changes its billing arrangement.

POS Coding Checklist for Medical Billing Teams

Before submitting a professional claim, ask:

• Where was the service actually provided?
• Was the service in person or telehealth?
• If telehealth, was the patient at home?
• Is the location an office, hospital, SNF, ASC, home, or another setting?
• If hospital-based, is the outpatient department on or off campus?
• Does the POS match the CMS definition?
• Does the payer have additional POS requirements?
• Does the POS make sense with the CPT/HCPCS code?
• Does the POS agree with the medical record?
• Could the POS affect facility/non-facility payment?
• Has the claim been checked for other payer-specific edits?

A few seconds spent verifying the location can be much cheaper than correcting a claim after submission.

Frequently Asked Questions About Place of Service Codes

What is a POS code in medical billing?

A POS code is a two-digit code used on professional claims to identify where a healthcare service was provided. CMS maintains the national POS code set.

What does POS 11 mean?

POS 11 means Office. It represents a location where a healthcare professional routinely provides ambulatory examinations, diagnosis, and treatment, outside the facility types excluded by CMS’s definition.

What is POS 22?

POS 22 means On-Campus Outpatient Hospital. It is used for outpatient hospital services provided on the hospital’s main campus when the CMS definition applies.

What is the difference between POS 19 and POS 22?

Both represent outpatient hospital settings. POS 19 is for an off-campus outpatient hospital, while POS 22 is for an on-campus outpatient hospital.

What is POS 02 vs. POS 10?

POS 02 is telehealth when the patient is not at home. POS 10 is telehealth when the patient is at home.

Does POS affect Medicare reimbursement?

It can. For certain services under the Medicare Physician Fee Schedule, POS helps determine whether facility or non-facility payment rates apply. The exact effect depends on the service and applicable payment rules.

Can the same provider use different POS codes?

Yes. A provider can use different POS codes when services are furnished in different settings. The POS should represent the actual setting of the service and comply with the payer’s requirements.

Is POS 99 a general code for an unknown location?

No. POS 99 means Other Place of Service, a setting not identified by another POS code. It should not simply be used because the billing team has not determined the correct setting.