Guides 6 min read
How to Choose a Peptide Vendor: A Researcher's Checklist
Practical criteria for evaluating peptide suppliers — from CoA quality to shipping reliability and community reputation.
DEM
Dr. Elena Marsh
Chief Science Officer
Before You Order
Choosing a peptide vendor is a critical decision that directly impacts your research quality. Here's what to evaluate:
The Checklist
✅ 1. CoA Quality
- •Does the vendor provide a CoA for every batch?
- •Does the CoA include both HPLC purity and mass spec data?
- •Is the CoA from an accredited lab?
✅ 2. Purity Standards
- •Is the stated purity ≥ 95% for research grade?
- •Are purity claims supported by chromatogram data?
✅ 3. Third-Party Verification
- •Is the vendor listed and verified on PepAssure?
- •What is their PVS score?
✅ 4. Community Reputation
- •Check r/Peptides and related forums
- •Look for consistent positive feedback over time
- •Be wary of vendors with only recent, suspiciously positive reviews
✅ 5. Transparency
- •Clear contact information and business address
- •Published return/refund policy
- •Responsive customer service
✅ 6. Shipping & Handling
- •Appropriate cold-chain shipping for temperature-sensitive peptides
- •Discrete packaging
- •Domestic vs. international shipping options
✅ 7. Pricing
- •Competitive but not suspiciously cheap
- •Bulk pricing available
- •Clear pricing without hidden fees
Red Flags
- •❌ No CoA available or "CoA available upon request" only
- •❌ Identical CoAs across different peptides or batches
- •❌ No verifiable business information
- •❌ Prices significantly below market average
- •❌ Aggressive marketing with medical claims