42 CFR § 408.3 - Definitions.

---
identifier: "/us/cfr/t42/s408.3"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "42 CFR § 408.3 - Definitions."
title_number: 42
title_name: "Public Health"
section_number: "408.3"
section_name: "Definitions."
chapter_name: "CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES"
subchapter_number: "B"
subchapter_name: "MEDICARE PROGRAM"
part_number: "408"
part_name: "PREMIUMS FOR SUPPLEMENTARY MEDICAL INSURANCE"
positive_law: false
currency: "2026-03-24"
last_updated: "2026-03-24"
format_version: "1.1.0"
generator: "[email protected]"
authority: "42 U.S.C. 1302 and 1395hh."
regulatory_source: "52 FR 48115, Dec. 18, 1987, unless otherwise noted."
cfr_part: "408"
---


# 408.3 Definitions.

As used in this part, unless the context indicates otherwise—

*Enrollee* means an individual who is enrolled in the SMI program under Medicare Part B.

*Taxable year* means the 12-month period (calendar or fiscal year) for which the individual files his or her income tax return.