How to reply to a COA request from a supplement brand (template + checklist)
When a supplement brand asks for your COA, it is usually not paperwork for its own sake. Under the US dietary supplement GMP rule (21 CFR Part 111), the brand has to show that every component meets its specifications. Your reply decides whether you get qualified as a supplier or quietly dropped.
Why the brand is asking
- Identity is on them. 21 CFR 111.75(a)(1) requires the manufacturer to run at least one appropriate test or examination to verify the identity of each dietary ingredient before use. Your COA does not replace that test, but your identity method (for example HPTLC or HPLC) tells them which test will agree with yours.
- Everything else can rest on your COA — if they qualify you. For other specifications, 111.75(a)(2)(ii) lets them rely on a supplier COA after qualifying the supplier: confirming your results, checking that the COA lists the methods, limits and actual results, documenting it, and re-confirming periodically.
- Importers verify suppliers too. Under the Foreign Supplier Verification Program (21 CFR Part 1, Subpart L), US importers of supplements and their components keep supplier verification records. A clean document set makes you the easy choice.
What a buyer-ready COA shows
- Product name, botanical name (Latin) and plant part
- Lot / batch number, manufacture date and retest or expiry date
- Each specification with its limit, actual result and test method — a COA that only says “conforms” is hard to qualify against
- Identity method (HPTLC, HPLC, macroscopy…)
- Heavy metals (Pb, As, Cd, Hg) and microbiology, with units
- Residual solvents and pesticide residues where you test them
- QA approval: name, signature and date
Send these with it
Spec sheet (TDS), SDS, allergen statement and non-GMO statement cover most first requests. Market-specific statements — Prop 65 for California, for example — are worth having ready, but only send what you can back up. If you don’t have one yet, say it is being confirmed; don’t say you don’t have it unless that is true.
Reply template
Subject: Panax Ginseng Extract 80% — COA, spec sheet and SDS (lot [LOT]) Hi [Name], Thanks for considering us. Attached for lot [LOT]: - COA (limits, results and methods) - Spec sheet (TDS) and SDS Answers to your questions: - Identity method: [method from your COA] - Heavy metals: Pb ≤ [x] ppm, As ≤ [x] ppm, Cd ≤ [x] ppm, Hg ≤ [x] ppm - Microbiology: TPC ≤ [x] cfu/g; yeast & mold ≤ [x] cfu/g; E. coli / Salmonella negative - Country of origin: [TBD: confirm] - Lead time for [quantity]: [stock or production lead time] Would a 20 g sample from the same lot help your identity test? Best regards, [Your name] [Company]
Four mistakes that cost the order
- Sending a COA from a different lot than the one you will ship.
- Sending a spec sheet and calling it a COA.
- Adding health benefits to a quality reply (“also helps lower blood sugar”) — see what ingredient suppliers can say.
- Rounding numbers or guessing the lead time. A brand that finds one wrong number re-checks all of them.
Try it on your own data: paste a buyer’s email and get a reply built from your spec sheet, with gaps marked [TBD] and disease claims blocked. Free plan included.
Paste a COA request into the workbench →FAQ
Can a supplement brand rely on my COA instead of testing?
For identity of a dietary ingredient, no: 21 CFR 111.75(a)(1) requires the manufacturer to verify identity itself. For other specifications it may rely on your COA after qualifying you as a supplier under 111.75(a)(2)(ii).
What should a COA include for US supplement customers?
Product and botanical name, lot number, dates, every specification with limit, actual result and test method, identity method, heavy metals, microbiology, and QA approval.
Should I mention health benefits when I send a COA?
No. Keep quality replies to specifications and documents. Claims on the finished product are the brand’s responsibility and must follow FDA and FTC rules.