Question 1

What is ICD-10 code Z09?

Accepted Answer

Z09 is the ICD-10-CM diagnosis code for encounter for follow-up examination after completed treatment for conditions other than malignant neoplasm. A patient is having a follow-up examination after completing treatment for a non-cancer condition to ensure recovery and monitor for complications. Z09 sits in the ICD-10-CM chapter for factors influencing health status and contact with health services (z00-z99), within the section covering persons encountering health services for examinations (z00-z13).

Z09 is a billable ICD-10-CM code but does not map to a payment HCC under the CMS-HCC V28, V24, ESRD, or RxHCC risk adjustment models. It can be reported on Medicare Advantage encounter data submissions but it does not contribute to a beneficiary's RAF score and therefore does not affect risk-adjusted payments to the plan.

This code covers follow-up visits for any completed treatment except malignant neoplasm; use Z08 for cancer follow-ups.

Question 2

Is Z09 an HCC code?

Accepted Answer

No. Z09 is a billable ICD-10-CM code but does not map to any payment HCC category under the CMS-HCC V28, V24, ESRD, or RxHCC risk adjustment models. It can still be reported on Medicare Advantage encounter data submissions, but it does not contribute to the beneficiary's Risk Adjustment Factor (RAF) score and therefore does not affect the risk-adjusted capitation payment to the plan. V28 reached 100% phase-in for payment year 2026.

Question 3

Is Z09 billable?

Accepted Answer

Yes. Z09 is a billable ICD-10-CM code that can be reported on professional and institutional claims as a primary or secondary diagnosis when the provider documentation supports the specific condition described. Billable codes in ICD-10-CM are coded to the highest level of specificity available for the documented diagnosis. Z09 is current for fiscal year 2026 and remains in the active CMS ICD-10-CM code set published by the National Center for Health Statistics.

Question 4

What is the V28 vs V24 difference for Z09?

Accepted Answer

Z09 does not map to a payment HCC under either the CMS-HCC V28 risk adjustment model or the older V24 model. V28 reached 100% phase-in for payment year 2026, replacing V24 which was used during the PY2024–PY2025 transition. Because neither model rewards Z09 with a risk adjustment factor, it contributes zero to a Medicare Advantage beneficiary's RAF score in either version. Coders should check whether provider documentation supports a more specific child code that does map to a payment HCC.

Question 5

What should coders know when reporting Z09?

Accepted Answer

This code covers follow-up visits for any completed treatment except malignant neoplasm; use Z08 for cancer follow-ups Document the original condition that was treated and the reason for the follow-up visit

Z09

Is Z09 an HCC code?

What This Code Means

Coding Tips

Excludes 1 — Do NOT code together

Use Additional Code

Code Hierarchy

Open Z09 in the Interactive Encoder