42 CFR § 423.512 - Minimum enrollment requirements.

---
identifier: "/us/cfr/t42/s423.512"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "42 CFR § 423.512 - Minimum enrollment requirements."
title_number: 42
title_name: "Public Health"
section_number: "423.512"
section_name: "Minimum enrollment requirements."
chapter_name: "CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES"
subchapter_number: "B"
subchapter_name: "MEDICARE PROGRAM"
part_number: "423"
part_name: "VOLUNTARY MEDICARE PRESCRIPTION DRUG BENEFIT"
positive_law: false
currency: "2026-04-05"
last_updated: "2026-04-05"
format_version: "1.1.0"
generator: "[email protected]"
authority: "42 U.S.C. 1302, 1306, 1395w-101 through 1395w-152, and 1395hh."
regulatory_source: "70 FR 4525, Jan. 28, 2005, unless otherwise noted."
cfr_part: "423"
---


# 423.512 Minimum enrollment requirements.

(a) *Basic rule.* Except as provided in paragraph (b) of this section, CMS does not enter into a contract under this subpart unless the organization meets the following minimum enrollment requirement:

(1) At least 5,000 individuals are enrolled for the purpose of receiving prescription drug benefits from the organization; or

(2) At least 1,500 individuals are enrolled for purposes of receiving prescription drug benefits from the organization and the organization primarily serves individuals residing outside of urbanized areas as defined in § 412.62(f) of this chapter;

(3) Except as provided for in paragraph (b) of this section, a Part D plan sponsor must maintain a minimum enrollment as defined in paragraphs (a)(1) and (a)(2) of this section for the duration of its contract.

(b) *Minimum enrollment waiver.* CMS waives the requirement of paragraphs (a)(1) and (a)(2) of this section during the first contract year for a sponsor in a region.