Summary & Overview
HCPCS Level II M1238: Documentation of Delayed Second Recombinant Zoster Dose
HCPCS Level II code M1238 documents that the second dose of the recombinant zoster vaccine could not be administered during the performance period because of the recommended 2–6 month dosing interval (for example, when the first dose was received after October 31). Nationally, this code standardizes reporting when a recommended series dose falls outside a program or reporting period, enabling consistent documentation for clinical records and payor review.
Key payers covered in this publication include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise explanation of what the code represents, the clinical context for delayed second-dose administration, and the typical sites where this documentation is recorded. The publication outlines common modifiers associated with vaccine and procedural reporting and summarizes available policy considerations and billing implications for major payers.
This analysis helps clinicians, billing staff, and policy teams understand how M1238 fits into vaccine-series documentation workflows, what to expect from payer coverage frameworks, and where to look for related codes and guidance. Data not available in the input is noted where applicable.
Billing Code Overview
HCPCS Level II code M1238 documents that administration of the second recombinant zoster vaccine could not occur during the performance period because of the recommended 2–6 month interval between doses (for example, when the first dose was received after October 31). This code represents a vaccine administration documentation/service related to the recombinant zoster vaccine series.
Service Type: Vaccine administration documentation for delayed second dose
Typical Site of Service: Outpatient vaccination settings, such as physician offices, clinics, and pharmacy-based vaccination sites.
Clinical & Coding Specifications
Clinical Context
A 68-year-old patient presented to a primary care clinic for routine immunization follow-up. The patient received the first dose of recombinant zoster vaccine (RZV, Shingrix) on November 15 during an annual visit. The clinic documents that the second dose cannot be administered within the current performance/reporting period because the recommended 2–6 month interval between doses places the due date after the program cutoff (dose two would fall in mid-January). Front-desk staff schedule the follow-up vaccination appointment within the recommended 2–6 month window and record the reason for delayed administration in the immunization record and the encounter note. The clinical workflow includes: verifying prior dose date, counseling the patient on timing and side effects, documenting the planned second-dose date, and using the specific HCPCS Level II billing code M1238 to indicate documentation that the second dose could not occur during the performance period due to the recommended interval.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
22 | Increased procedural services | Use when documentation supports substantially greater work for vaccine counseling or complex vaccine-related decision-making beyond typical time. |