Peptide Plugs and NextGenPeps are our two highest scorers, and only 0.1 apart on our transparency method (8.1 vs 8.0). Peptide Plugs leads on verification: its product pages give a lab accession code you can search on Freedom Diagnostics' own site. NextGenPeps leads on labeling: it names its two labs on every COA entry and avoids benefit-named shop categories. Neither has independent test data as of September 26, 2026. NextGenPeps is #2 and Peptide Plugs #5 in our editors' order, which isn't sorted by score.
Notice: Both vendors sell products for in-vitro 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.
Side-by-side
| NextGenPeps | Peptide Plugs | |
|---|---|---|
| Transparency score (method) | 8.0 | 8.1 |
| Entity and address | NUTRL LLC, 1331 Columbia St, San Diego, CA | Austin Research Products LLC, 126 Holmes Rd #8, Liberty Hill, TX |
| Business age | Founded 2025; domain April 2025 | Domain registered December 2025 |
| COA format | ~49 dated entries with purity; some endotoxin | 117 dated COAs, 62 products, purity and measured content |
| Lab named | Janoshik and BioRegen, on each entry | Freedom Diagnostics, on site and each entry |
| Lab-side check | Both labs run public lookups; report number needed | Accession code on product pages, linked to lab search |
| Lot numbers | Not shown in library | On product pages, not main COA page |
| Finnrick | No profile | Profile, 0 tests |
| Naming issues | GLP-RT, GLP-TZ, GLP-S | "Weight Loss"/"Anti-Aging" categories; "GLP3 + Elora" |
| Free shipping | Over $150 (USPS) | Over $200 (UPS) |
| Payment | Cards, PayPal, Apple Pay | Credit card |
| Returns | Wrong items reshipped; loss/damage case by case | All sales final; damage within 7 days |
| FDA warning letter | None found | None found |
Sources: NextGenPeps homepage, NGP COA library, NGP terms, NGP shipping, NGP reship policy, Peptide Plugs COAs, PP terms, PP shipping, PP refund policy, Finnrick: Peptide Plugs, FDA warning letters.
COAs and lab verification
Both name their labs on their own COA pages, which only three of the eight vendors we review do (Licensed Peptides is the third).
Peptide Plugs has more certificates and a more direct check. Its COA page listed 117 certificates across 62 products, each dated with purity and measured content. Product pages list a lot and an accession code. The GLP3 + Elora page, for example, shows lot 56440-RB and code Pept2609159124, with a link to Freedom Diagnostics' COA search. Because the lookup runs on the lab's site, it's a stronger check than a PDF alone. We found no sterility or endotoxin reports.
NextGenPeps has fewer entries but more kinds of data. Its COA library had about 49 entries, roughly three-quarters from BioRegen and the rest from Janoshik, dated July 2025 to June 2026. Some include endotoxin results. The library doesn't show lot numbers or verification keys, so you'll need the report number from the PDF to use Janoshik's or BioRegen's lookup, and support to match a report to your lot.
On our scale, Peptide Plugs leads on both COA publication (9.25 vs 8.5) and lab traceability (9.0 vs 8.75). Our COA guide covers the checks.
Independent testing: a tie at zero
Finnrick tracks Peptide Plugs but shows 0 tests. We found no Finnrick profile for NextGenPeps. Both get the floor score (5.0). Peptide Plugs' about page offers $100 store credit for verified COAs from Freedom Diagnostics, Finnrick or Janoshik, but we found no published results from it. See Janoshik vs Finnrick.
Labeling
Both use strict research-use disclaimers. NextGenPeps' terms bar buyers from administering products to humans or animals, and Peptide Plugs' footer says it makes "no health, dosing, or therapeutic claims of any kind." Neither showed dosing content on the pages we reviewed.
The deductions differ:
- NextGenPeps sells three GLP-1-class products under codes only: GLP-RT, GLP-TZ and GLP-S.
- Peptide Plugs organizes its shop into categories named "Weight Loss," "Anti-Aging," "Sleep" and "Vitality." The Weight Loss category had 12 items. It also sells a coded GLP-1-class blend ("GLP3 + Elora") and some tablets.
NextGenPeps scores better here (8.25 vs 7.5). Benefit-named categories are the kind of marketing FDA has cited against research-use sellers (background). We cover GLP-1-class products for research use only, with no dosing content.
Business details, shipping and payment
Both publish a named LLC and a street address, and both scored 9.5 on business transparency.
- NextGenPeps ships by USPS within 1-3 business days from California, free over $150, to all 50 states, Puerto Rico and US territories. It lists Visa, Mastercard, Amex, Discover, PayPal and Apple Pay, and guarantees a reship for wrong items.
- Peptide Plugs ships by UPS within 1-2 business days from Liberty Hill, TX, free over $200, US only. Its terms mention credit card checkout. All sales are final, with damage reported within 7 days for a replacement or store credit.
Price and offers
Neither has a PeptideChecked code. When we checked, NextGenPeps had BPC-157 5mg at $37 and TB-500 10mg at $58 on sale, plus 10% off a first order for email sign-up (shop). Peptide Plugs listed BPC-157 20mg at $50 and TB-500 10mg at $50, with a points program and bundle discounts (shop). Vial sizes differ, so compare per milligram. See peptide coupon codes for current offers.
Reputation and lookalikes
NextGenPeps' Trustpilot page had 21 reviews averaging 3.1/5, split between 5-star and 1-star. We found no Trustpilot page for Peptide Plugs. Both have lookalikes: NextGen Peptides (ngpeptide.com) is a separate company, and The Peptide Plugs describes itself as a Canadian store.
Which should you choose?
- If you want to verify a certificate at the lab yourself, Peptide Plugs is the stronger choice and scores slightly higher. Visit Peptide Plugs.
- If you want endotoxin data on some batches, cleaner naming, PayPal or US-territory shipping, NextGenPeps is ahead. Visit NextGenPeps.
Either way, get the report that matches your lot, confirm it at the lab, and watch for Finnrick data. For lab-handling unit math, use our reconstitution calculator.
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