21 CFR Part 111: What Brands Need to Know
If you sell dietary supplements in the United States, the manufacturers you work with must comply with 21 CFR Part 111. This guide explains what Part 111 requires in plain language — no regulatory jargon, no legalese.
Dietary supplement manufacturers must comply with 21 CFR Part 111 — Current Good Manufacturing Practice for dietary supplements. This includes requirements for personnel, facilities, equipment, production, laboratory operations, and record-keeping.
What Part 111 Is
21 CFR Part 111 is the FDA regulation that establishes Current Good Manufacturing Practice (cGMP) for dietary supplements. It was finalized in 2007 and applies to every company that manufactures, packages, labels, or holds dietary supplements sold in the United States.
The regulation covers the entire manufacturing process — from receiving raw materials to shipping finished products. Its purpose is to ensure that dietary supplements are produced consistently, meet quality standards, and contain what their labels say they contain.
Who It Applies To
Part 111 applies to every domestic and foreign facility that manufactures, packages, labels, or holds dietary supplements for sale in the U.S. This includes:
- Contract manufacturers (CMs) who produce supplements for brands
- Co-packers who package or label products
- Warehouses and distribution centers that hold dietary supplements
- Brands that manufacture their own products in-house
As a brand, you don't directly comply with Part 111 unless you manufacture in-house. But you're responsible for choosing manufacturers who do comply. If your CM isn't cGMP-compliant, your products are non-compliant.
The Eight Subparts of Part 111
Part 111 is organized into eight subparts. Here's what each one covers in plain language.
Subpart B — Personnel
People who work in supplement manufacturing must be qualified for their jobs and trained in cGMP, hygiene, and their specific responsibilities. The regulation requires a designated quality control person with education, training, or experience to make quality decisions.
Subpart C — Physical Plant and Grounds
Manufacturing facilities must be designed and maintained to prevent contamination. This covers building design, water systems, plumbing, sewage, pest control, cleaning, and sanitation. Separate areas are required for different operations to prevent cross-contamination.
Subpart D — Equipment and Utensils
All equipment used in manufacturing must be appropriate for its intended use, maintained in a clean and sanitary condition, and calibrated regularly. Automatic, mechanical, and electronic equipment must be routinely inspected and validated.
Subpart E — Requirement to Establish a Production and Process Control System
Manufacturers must have a written production and process control system. This includes master manufacturing records (the recipe), batch production records (what actually happened), and procedures for every step from receiving materials to releasing finished product.
Subpart F — Production and In-Process Control System
This is the detailed "how" of manufacturing. It covers receiving and inspecting raw materials, identifying and holding components, producing supplements according to the master record, sampling and testing during production, handling reprocessing, and managing rejected materials.
Subpart G — Laboratory Operations
Testing requirements for raw materials and finished products. Labs must use scientifically valid methods, maintain proper records, and test for identity, purity, strength, and composition. Manufacturers can use in-house labs, contract labs, or both.
Subpart H — Holding and Distribution
Requirements for storing components and finished products under appropriate conditions (temperature, humidity, light). Distribution records must be maintained to enable product recalls when necessary.
Subpart I — Records and Recordkeeping
Detailed requirements for what records must be kept and for how long. This includes batch records, lab results, complaint files, and returned product records. Most records must be retained for at least one year beyond the product's shelf life.
Common FDA Violations
FDA publishes warning letters and inspection observations (Form 483s) publicly. Based on these records, the most common Part 111 violations include:
- Failure to establish product specifications. Not defining what the finished product should contain, including identity, purity, strength, and composition limits.
- Failure to test components for identity before use. Using raw materials without confirming they are what the supplier says they are.
- Failure to establish and follow written production procedures. No master manufacturing records, or manufacturing that deviates from written procedures without documentation.
- Inadequate testing of finished products. Releasing products without testing for identity, purity, strength, composition, and contamination.
- Inadequate batch production records. Incomplete documentation of what happened during production — missing times, temperatures, quantities, or personnel records.
- Failure to investigate complaints and adverse events. Not maintaining a system to receive, evaluate, and respond to product complaints.
Source: FDA warning letters and 483 observations are publicly available on the FDA website.
What This Means for Brands
If you're a brand working with contract manufacturers, Part 111 compliance should be a baseline requirement, not a bonus. Here's what you should do:
- Confirm your CM is FDA registered and can provide their registration number
- Ask for their most recent third-party cGMP audit report
- Request documentation of their production and process control system
- Verify they test raw materials for identity and finished products for specifications
- Review their complaint handling and adverse event reporting procedures
- Include cGMP compliance requirements in your manufacturing agreement
For a complete framework on evaluating manufacturers, see our guide to evaluating supplement manufacturers.
Disclaimer: This guide is educational content based on publicly available FDA regulations and enforcement records. It is not legal or regulatory advice. The full text of 21 CFR Part 111 is available on the Electronic Code of Federal Regulations. Consult qualified regulatory counsel for compliance guidance. See our Terms of Service.