The manufacturer you choose determines your product's quality, compliance and consistency — not just the price per bottle. Here is a practical checklist to evaluate a dietary supplement contract manufacturer before you commit.

1. Start with manufacturing credentials

Ask for evidence of GMP-compliant production. "GMP" (Good Manufacturing Practice) describes the system of controls used to ensure products are consistently produced and controlled to quality standards. Ask which GMP framework applies (for example, US cGMP under 21 CFR Part 111 for products sold in the US), and ask for the facility's registration or audit documentation.

2. Verify what FDA registration actually means

For US-bound products, many buyers ask whether the supplier holds US FDA facility registration. Registration confirms the establishment is listed with the FDA — it is an establishment listing, not a product approval or certification. You can verify a supplier's registration number on the FDA's public database. Always read the official wording carefully and ask the supplier to explain their registration scope.

3. Ask about testing and documentation

Quality is only as good as what is measured. Ask these questions:

  • Do you issue a Certificate of Analysis (COA) with every batch?
  • What tests are run per batch — identity, assay, purity, microbiological?
  • Can you provide heavy-metal and microbial test reports?
  • Are batch records retained and traceable?
  • What export documentation is included (commercial invoice, packing list, test reports)?

4. Understand the MOQ and pricing structure

Minimum order quantities vary by dosage form and packaging. A genuine trial-batch MOQ (for example, from 100 units per SKU) lets you validate the market before scaling. Ask for a transparent price breakdown at trial volume and at scale — and ask what changes with custom packaging.

5. Order samples before bulk

Working samples are the single best verification tool. Check the sampling time (3–5 days is a strong benchmark), whether samples are free, and whether the sample matches the final production spec — same formula, same packaging, same labeling approach.

6. Check communication and project management

Your supplier should assign one dedicated account manager, respond within a defined time (one hour is a good benchmark), and give you clear milestones: brief → sample → production → inspection → shipment. A supplier that communicates clearly before the order will communicate clearly during it.

7. Confirm compliance planning for your market

Supplement labeling and registration requirements differ by destination. A good partner asks about your target market first and plans documentation accordingly — not as an afterthought. Ask what they need from you to prepare your import documentation.

8. Visit or request a facility walkthrough

Many exporters offer video tours or photo documentation of their production lines, QC laboratory and warehousing. It is a simple way to confirm the facility exists and matches the description before you order.

How Haiyue Shengda measures up

We are a dietary supplement OEM/ODM manufacturer based in Shaanxi, China, producing in our own factory. We issue a COA with every batch, hold a current US FDA facility registration (No. 11057149244), offer trial-batch MOQs from 500 units, deliver free samples in 3–5 days, and assign one dedicated account manager per project. Contact us — we respond within one hour.