What is a Notice of Proposed Rulemaking (NPRM)?

A Notice of Proposed Rulemaking, or NPRM, is the formal document an agency publishes in the Federal Register to propose a new regulation and open it for public comment. The Administrative Procedure Act of 1946 requires most substantive federal rules to go through this process: NPRM, public comment period, agency response, and final rule.

A typical NPRM contains: the legal authority (the statute Congress passed letting the agency regulate this), the proposed regulatory text, a preamble explaining the agency's reasoning, a cost-benefit analysis, a Regulatory Flexibility Analysis covering small-entity impact, and a comment deadline. NPRMs are numbered by docket (e.g., EPA-HQ-OAR-2024-0234) and assigned a Regulatory Identifier Number (RIN) that tracks them in the Unified Agenda.

After the comment period closes (usually 30–60 days), the agency reviews comments, often revises the rule, and sends a final rule to OIRA for review. The final rule publishes in the Federal Register with an effective date — typically 30 to 60 days after publication for most rules, 60 days for major rules ($100M+ economic impact) under the Congressional Review Act.

Not every rule requires an NPRM: interpretive rules, policy statements, and "good cause" emergency rules can skip notice-and-comment. Those exceptions are litigated frequently.