Swiss Chems and PSPeptides score close on our transparency method (7.2 vs 7.0), for opposite reasons. Swiss Chems has operated since 2018 and has independent Finnrick data. But it received an FDA warning letter in December 2024, and only 4 of 10 Finnrick samples passed. PSPeptides has no FDA letter as of September 26, 2026. But its blog publishes human dosing guides, it has no independent data, and several of its claims are hard to verify.
Notice: Both vendors sell products for laboratory research only. They are not FDA-approved and not for human or animal consumption. This comparison covers supplier transparency only, based on public documentation. We didn't purchase or test products, and we don't repeat dosing content.
Side-by-side
| Swiss Chems | PSPeptides | |
|---|---|---|
| Transparency score (method) | 7.2 | 7.0 |
| Stated location | "Est. 2018 — USA"; no address on site | New Jersey; Paramus suite address on Trustpilot |
| Business age | Since 2018 (per site) | Claims 5+ years; domain registered Nov 2025 |
| FDA warning letter | Yes, December 10, 2024 | None found |
| Finnrick | 48%, #341 of 345, 4 of 10 passed | Profile, 0 tests |
| COA page | 60 dated reports, batch codes in file names | ~60 products, dated by month, test IDs |
| Lab named | "Principally Janoshik" (FAQ only) | Not on site; North American Diagnostics on the PDF we opened |
| Dosing or benefit content | None seen now; FDA cited past marketing | Dosing guides; "Shred Express," "Turn Back Time" bundles |
| Free shipping | Over $100 US / $300 intl | Over $200 (UPS 2nd Day Air) |
| Payment | Mastercard, ACH/Zelle via processor, crypto | Cards, Apple/Google/Shop Pay, Cash App, Zelle, Afterpay, Klarna |
| Returns | Sealed items, 7 days, 15% restocking + $25 fee | Not detailed on pages we reviewed |
Sources: Swiss Chems about, Swiss Chems test results, Swiss Chems FAQ, Swiss Chems shipping, Finnrick: Swiss Chems, PSPeptides about, PSPeptides certifications, PSPeptides payments, Finnrick: PSPeptides, PSPeptides WHOIS.
Regulatory record
This is the biggest difference. FDA's letter to Swisschems said its semaglutide and retatrutide were unapproved new drugs. It said the website and social media showed human-use intent despite "research chemicals only" labeling. Those products didn't appear in a store search on September 26, 2026, but the letter stays on the record.
PSPeptides has no FDA letter we could find. Its current content, though, is the kind FDA has pointed to in past letters. The blog's retatrutide page is titled "Week-by-Week Chart," and the Shred Express bundle is described as "designed for multi-pathway fat loss and metabolic research." We score what's on the record and what's on the page. Swiss Chems gets the floor score (5.0) for regulatory record, and PSPeptides gets 5.75 for labeling, both on our 5-10 scale. Background: FDA peptide regulation in 2026.
COAs and labs
Both post a lot of certificates, and neither names its lab on the COA page itself.
- Swiss Chems' results page had 60 entries, many dated September 2026, with batch codes in the file names. The FAQ says testing is "principally Janoshik Analytical." If a report is from Janoshik, you can confirm it with Janoshik's verify tool. Third-party audits report misfiled COAs (VialAudit).
- PSPeptides' certifications page covers about 60 products, dated by month. The certificate we opened came from North American Diagnostics, with a batch number and 99.96% purity. It listed no accreditation or verification key. PSPeptides' own "Verify" page looks up orders, not certificates.
Slight edge to Swiss Chems here, because its FAQ names a lab with a known public verification tool. See how to read a peptide COA.
Independent testing
Swiss Chems is the only one with data, and the data is weak. Finnrick shows 10 tests from April 2025 to April 2026, with 4 passing. CJC-1295 had repeated purity misses and underfills. BPC-157 passed 2 of 3, including the most recent test. PSPeptides has a Finnrick profile with no tests. Weak data still earns more than none on our transparency method (6.75 vs the 5.0 floor on this factor), because it's evidence the vendor doesn't control (why).
Business details and claims
Swiss Chems publishes no address or legal entity on its site. Its card charges appear under a processor name ("OPTIMUS DATA"), per its FAQ. PSPeptides says it's New Jersey-based with a 25-person team and claims US cGMP manufacturing and "over 5 years in business." Its domain was registered in November 2025, and we found nothing to verify the manufacturing claim.
Shipping, payment and reputation
PSPeptides is easier to pay: it takes cards, wallets, Cash App, Zelle and buy-now-pay-later. It ships free by UPS 2nd Day Air over $200 and to several countries. Swiss Chems ships worldwide, but seized packages get only a 30% discount, with no refund or reship. Its payment options run through third-party processors.
On Trustpilot, PSPeptides had 4.2/5 from 175 reviews on a profile that invites reviews (Trustpilot). We couldn't load Swiss Chems' Trustpilot page. A 2026 review describes Reddit sentiment on Swiss Chems as mixed (PeptideDeck).
Bottom line
Neither is a strong pick on transparency, and both score below the other six vendors on our list.
- Swiss Chems has more history and some independent evidence, plus an FDA warning letter. Visit Swiss Chems.
- PSPeptides has a clean FDA record so far and easy checkout, but its dosing content conflicts with research-use labeling. Visit PSPeptides. Our partner code CHECKED gives 10% off; we may earn a commission if you use it, and it doesn't affect the transparency score.
For vendors with higher transparency scores, see Peptide Plugs (8.1), NextGenPeps (8.0), American Peptides (7.6), Alpha Pro Peptides (7.5) and Ascension Peptides (7.4), or American Peptides vs NextGenPeps.