CMS Principal Illness Navigation Codes, Explained

Principal Illness Navigation, usually shortened to PIN, is a set of Medicare services established by CMS in the Calendar Year 2024 Medicare Physician Fee Schedule final rule that pay a billing practitioner for navigation support delivered to a patient who has a serious, high-risk condition. In plain terms, PIN is the mechanism that lets a practice bill Medicare for the work a patient navigator already does: assessing what is getting in the patient's way, explaining the treatment plan, coordinating appointments and referrals, and staying in contact between visits. The same rule created a companion service, PIN-Peer Support, for patients whose serious condition is a behavioral health condition, and a separate but related service called Community Health Integration for unmet health-related social needs.

This guide explains the structure of the PIN services in plain language: who may furnish them, what has to happen before you bill, what the documentation has to show, and where the common misreadings are. It is a general reference, not legal, coding, or billing advice. Rates, code descriptors, and requirements are revised annually, so confirm every detail against current CMS guidance and your own compliance counsel before you build a program around it.

What problem the PIN codes were created to solve

Navigation has existed as a clinical practice for decades, but for most of that time it was funded by grants, by hospital community benefit dollars, or by nothing at all. Programs would demonstrate value, then disappear when a grant cycle ended. CMS addressed that gap in the CY2024 Physician Fee Schedule final rule by recognizing navigation work as a distinct, separately payable service furnished by auxiliary personnel under a billing practitioner.

That is why the PIN codes matter beyond coding departments. They convert navigation from a program justified every budget cycle into a service line with a revenue mechanism. If you are new to the underlying practice, start with our overview of what patient navigation is and what navigators actually do.

Who counts as a patient with a serious high-risk condition

PIN is not for every patient with a chronic condition. CMS scoped it to patients with a serious, high-risk condition, and the description in the final rule has several parts that work together. The condition is expected to last a meaningful period of time, generally at least three months. It places the patient at significant risk of a bad outcome such as hospitalization, nursing facility placement, acute exacerbation or decompensation, functional decline, or death. And it requires development, monitoring, or revision of a disease-specific care plan, or it requires substantial assistance from a practitioner because of the complexity of the treatment or the decisions involved.

Cancer is the example CMS used most often, because a new cancer diagnosis is the classic case of a patient facing a complicated, high-stakes treatment path. But the definition is not cancer-specific. Serious heart, lung, kidney, neurologic, and behavioral health conditions can all meet it. The judgment about whether a given patient qualifies belongs to the billing practitioner and should be recorded.

Who may furnish PIN services

This is the part most people get wrong. The billing practitioner is a physician or other practitioner who can bill evaluation and management services, but the navigation work itself is furnished by auxiliary personnel, incident to that practitioner's services, with general supervision permitted rather than the direct supervision older incident-to rules required.

CMS declined to require a single national credential for those personnel. Instead, the rule describes them functionally: certified or trained navigators, patient navigators, care navigators, and, for the peer support version, certified peer support specialists. Where a state has a certification program, a state certificate is one way to satisfy the training expectation. Where it does not, the practice should be able to show the person has training appropriate to the tasks performed.

• The auxiliary personnel do not have to be employees of the billing practice. They may be contracted, including from a community-based organization.
• Only one practitioner may bill the service for a given patient in a given calendar month.
• For PIN-Peer Support, the person furnishing the service is a certified peer support specialist, meaning someone with lived experience of the behavioral health condition who holds a state or comparable peer certification.

The initiating visit requirement

PIN cannot begin out of nowhere. The service has to follow an initiating visit with the billing practitioner, at which the practitioner establishes that the patient has a serious high-risk condition, determines that navigation is medically necessary, and obtains the patient's consent. In practice this is an evaluation and management visit, an annual wellness visit, or a comparable qualifying visit, and it is where the plan for navigation is first documented.

Getting this wrong is the most common structural error in a new PIN program. Practices stand up a navigation team, deliver good service, then discover months later that the initiating visit was never documented as such.

Consent and patient cost sharing

The patient has to agree to receive the service. CMS permits consent to be obtained verbally, but it must be documented in the medical record, and the practitioner is expected to explain several things at the time consent is taken.

1. What the service is and what the navigator will do.
2. That the service is voluntary and the patient may stop it at any time, effective at the end of the calendar month.
3. That only one practitioner may furnish and bill the service in a calendar month.
4. That standard Medicare Part B cost sharing applies, meaning the patient may owe a deductible and coinsurance amount.
5. Consent is documented in the medical record and is generally obtained again on an annual basis, so build a renewal step into the workflow rather than treating consent as one-time.

The cost-sharing conversation is not a formality. For a patient already facing the financial weight of a serious illness, an unexplained new line on a statement is a reason to disengage.

Code structure, time, and what the documentation must show

The PIN services are billed with HCPCS Level II codes established in the CY2024 rule, structured as time-based, calendar-month services. G0023 covers principal illness navigation services by certified or trained auxiliary personnel under the direction of a physician or other practitioner, 60 minutes per calendar month, and G0024 is the add-on for each additional 30 minutes in the same month. PIN-Peer Support uses its own parallel pair, G0140 for the first 60 minutes furnished by a certified peer support specialist and G0146 for each additional 30 minutes, so peer-delivered support is distinguishable in claims data from navigation delivered by a patient navigator. Because descriptors, time thresholds, and payment amounts are revisited each rulemaking cycle, verify the current codes in the current fee schedule rather than any secondary summary, including this one. Later rulemaking has already adjusted the family: in the CY2026 Physician Fee Schedule final rule CMS revised the Community Health Integration descriptor to refer to upstream drivers rather than social determinants of health, clarified that marriage and family therapists and mental health counselors may bill CHI and PIN for the diagnosis or treatment of mental illness, and confirmed that identifying an unmet social need is not a required element of the PIN initiating visit. The PIN code set itself was not restructured.

What the documentation needs to demonstrate is more stable than the codes themselves. Across the PIN service elements described in the rule, a defensible record generally shows:

• A person-centered assessment of the patient's needs, goals, preferences, and barriers.
• Identification and facilitation of resources, including practical help getting to care, understanding it, and following through on it.
• Health education specific to the patient's condition and treatment, delivered at a level the patient can act on.
• Building the patient's self-advocacy skills so they can communicate with the care team directly.
• Health care access and system navigation, including coordination across settings and practitioners.
• Facilitation of behavioral change and social and emotional support related to the condition.
• Communication back to the billing practitioner, and time recorded against the calendar month.

How PIN differs from Community Health Integration

The same final rule created Community Health Integration, or CHI, and the two are frequently confused. The simplest distinction is what the service addresses. PIN addresses navigating a serious, high-risk illness. CHI addresses unmet health-related social needs, such as housing instability, food insecurity, or lack of transportation, that are interfering with the practitioner's diagnosis or treatment of the patient. CHI is typically furnished by community health workers, and it requires that the social need be identified and documented, generally through a social needs assessment, at the initiating visit.

Both rely on the same structure of an initiating visit, auxiliary personnel under general supervision, documented consent, and calendar-month time, and many organizations deliver both. Our guide to patient communication and texting workflows in FQHC settings covers the outreach side of that work.

Operational realities of running a billable navigation program

The service is billable per calendar month, so the operating unit of a PIN program is the month, not the encounter. Programs that succeed build three things early. First, a reliable way to capture navigator time in a system the billing team can pull from. Second, a documented list of who on the team is trained for which tasks, so a payer question about auxiliary personnel qualifications has an answer on file. Third, a contact cadence the patient tolerates, since a navigation month with no successful patient contact is both a billing problem and a care problem.

That last point is where communication tooling matters. Reaching a patient reliably between visits, on the channel they answer, is the operational bottleneck in most navigation programs.

Frequently Asked Questions

What is Principal Illness Navigation?

Principal Illness Navigation is a Medicare service, established in the Calendar Year 2024 Medicare Physician Fee Schedule final rule, that pays a billing practitioner for navigation support furnished to a patient with a serious, high-risk condition. The navigation itself is delivered by auxiliary personnel such as a trained patient navigator, incident to the practitioner's services and under general supervision.

Who can bill for Principal Illness Navigation?

The billing practitioner is a physician or other qualified practitioner who can bill evaluation and management services. They do not personally deliver the navigation. The service is furnished by auxiliary personnel, including certified or trained navigators and, for the peer support version, certified peer support specialists, working under the billing practitioner's supervision.

Does a patient navigator need a certification to bill PIN?

CMS did not impose a single national credential. The rule describes personnel functionally as certified or trained navigators. Where a state operates a certification program, that certificate is one way to demonstrate qualification. Where it does not, the practice should be able to document that the person has training appropriate to the tasks performed.

Is an initiating visit required before billing PIN?

Yes. Navigation services must follow a qualifying initiating visit with the billing practitioner, where the serious high-risk condition is established, the medical necessity of navigation is determined, and patient consent is obtained and documented. Skipping or failing to document that visit is the most common reason a month of otherwise good navigation work is not billable.

Does the patient pay anything for PIN services?

Standard Medicare Part B cost sharing applies, so the patient may owe a deductible and coinsurance. CMS expects the practitioner to tell the patient about cost sharing when consent is obtained. Many programs script that conversation and confirm it in writing afterward so patients are not surprised by a later statement.

What is the difference between PIN and Community Health Integration?

PIN addresses navigating a serious, high-risk illness. Community Health Integration addresses unmet health-related social needs, such as housing, food, or transportation, that interfere with diagnosis or treatment. CHI is usually furnished by community health workers and requires the social need to be identified and documented. Both share the initiating visit and supervision structure.

What is PIN-Peer Support?

PIN-Peer Support is the companion service for patients whose serious high-risk condition is a behavioral health condition. It is furnished by a certified peer support specialist, meaning a person with lived experience of the condition who holds a peer certification, and it is billed with its own codes so peer-delivered support is distinguishable in claims data.

Are the PIN payment rates fixed?

No. Payment amounts, code descriptors, and time thresholds are revisited in each annual Medicare Physician Fee Schedule rulemaking cycle. Always confirm current values against current CMS guidance rather than a secondary summary, and involve your compliance and billing leadership before building a program around a specific expected rate.

If your navigation team is losing hours to phone tag between visits, FRANSiS is a two-way patient texting platform built for healthcare organizations, with an AI Powered Helper that drafts replies for your staff to review and send, HIPAA compliance supported, and a signed BAA included. Talk to us about how it fits your navigation workflow, or read more about our healthcare communication approach.