Best MK-677 (Ibutamoren) Sellers in the UK – 2026 Review
We ordered MK-677 from the five most visible UK-based sellers and evaluated each product on purity verification, manufacturing standards, formulation quality, transparency, and real customer feedback. One brand stood out clearly. Most didn't.
How We Evaluated Each Brand
A 2017 JAMA study found that only 52% of products sold as SARMs actually contained the listed compound. That means nearly half the market is selling something other than what's on the label. With those odds, how a seller proves their product is real matters more than anything else. We scored each brand across six categories, weighted by how much they actually protect the buyer.
Purity & Lab Verifiability 30%
Is the product independently tested? Is the lab named so results can be verified independently? A high purity number from an unnamed lab carries less weight than a slightly lower number from a named, contactable lab.
Manufacturing Standards 25%
Where and how is the product made? GMP certification, cleanroom grades (ISO 7 vs. ISO 9001), and quality control documentation.
Formulation & Absorption 15%
Does the product include any bioavailability enhancers? Capsule vs. liquid? Dosing precision and convenience.
Transparency & Trust 15%
Can you verify claims independently? Named labs, visible COAs, company registration, community reputation, clear research-only positioning.
Customer Reviews 10%
Volume, average rating, recency, and specificity of reviews. We score on what's publicly visible and verifiable on the product page.
Value for Money 5%
Price per unit, cost per mg, and whether the price reflects the quality of manufacturing and testing behind it.
The Rankings
CORE SARMs
The only brand on this list that combines named lab verification (Janoshik Analytical), ISO 7 cleanroom manufacturing, and a piperine absorption enhancer in the formulation. No other UK MK-677 seller offers all three. Tested at 99.2%+ purity with batch-specific COAs on every product page. £45 for a 2-month supply at standard dosing - £0.75/day.
147 reviews averaging 4.86/5 with unusually detailed feedback. Wartorn edges them on average score (4.92), but CORE's reviews are longer and cover more use cases.
Strengths
- Named lab testing (Janoshik) - independently verifiable
- ISO 7 cleanroom + GMP-certified facility
- Only brand with piperine for enhanced absorption
- Batch-specific COAs on every product page
- 147 detailed customer reviews (4.86/5)
- UK-based company with registered address
- Highest Reddit community presence of any UK seller
Limitations
- No multi-buy discount currently visible
- Newer brand compared to some established sellers
Wartorn (Affordable Nutrition)
Solid runner-up. Lowest price (£39.95), highest dose per capsule (12.5mg), and the highest tested purity number on this list (99.38%). 142 verified reviews at 4.92/5. ISO 9001 manufacturing with QR-code verification on packaging. Great customer service and same-day dispatch.
The gap: the testing lab is not named publicly, so buyers can't independently verify the purity result. No bioavailability enhancer, and ISO 9001 (quality management) isn't the same as ISO 7 (cleanroom sterility). A genuinely good product - the verifiability gap is what keeps it from #1.
Strengths
- Lowest price on this list (£39.95)
- Higher dose per capsule (12.5mg)
- Highest tested purity number (99.38%)
- Highest average review score (4.92/5, 142 verified)
- Same-day dispatch, excellent customer service
- QR codes on packaging for authenticity
Limitations
- Testing lab not named - results cannot be independently verified
- No absorption enhancer in formulation
- ISO 9001 (management), not ISO 7 (cleanroom)
- Brand name inconsistency (Wartorn vs. Affordable Nutrition)
Receptorchem
The longest-running UK supplier (est. 2011). Liquid format, 30ml at 25mg/ml, £49.99. Lists >99% purity with HPLC-verified COAs and chromatography data visible on the product page. Decent testing documentation. Longevity counts for something.
Trade-offs: liquid dosing is less precise than capsules. No manufacturing certifications listed, minimal on-site reviews, dated website, no absorption enhancer. Trusted legacy supplier with real lab docs, but the experience hasn't kept pace.
Strengths
- Longest-running UK supplier (est. 2011)
- HPLC-verified COAs with chromatography data visible
- Higher total MK-677 content (750mg per bottle)
- 10% discount on multi-buy
- Established Reddit community presence
Limitations
- Liquid format - less precise dosing
- No manufacturing certs (GMP/ISO) publicly listed
- Very few on-site customer reviews
- Dated website and user experience
- No absorption enhancer
UKSARMs
Claims to be "The UK & Europe's #1 SARMs Supplier." Liquid format at £59.99 - the most expensive option by a wide margin. Batch verification through two independent US labs is a decent transparency signal.
At nearly £60, the price is 33-50% higher than comparable products. Liquid dosing, no visible customer reviews, no manufacturing certs, and the "#1" claim has no backing methodology. Premium pricing needs premium proof - the evidence doesn't justify the cost.
Strengths
- Two independent US labs for verification
- Detailed product information on site
- Established brand presence
Limitations
- Highest price on this list (£59.99)
- Liquid format - imprecise dosing
- No visible customer reviews
- "#1 Supplier" claim with no backing evidence
- No manufacturing certs listed
- No absorption enhancer
Thoroughbred Labs
£44.99 for 60 capsules at 12.5mg. References a COA section and heavy metals testing. Capsule format is a plus for dosing precision.
The problem: no purity percentage listed anywhere. Zero customer reviews on site, no manufacturing certifications, and the product page is mostly legal disclaimers. In a market where purity verification is everything, this level of opacity is a real concern.
Strengths
- Capsule format with higher 12.5mg dose
- Heavy metals testing referenced
- Competitive pricing
Limitations
- No purity percentage listed publicly
- Zero customer reviews on product page
- No manufacturing certifications mentioned
- Minimal product information beyond disclaimers
- No absorption enhancer
- No Reddit presence found
Community Presence: Reddit Mentions
We tracked Reddit discussions across r/sarms, r/SARMsUK, r/PEDs, and r/moreplatesmoredates to see which brands UK buyers actually talk about. Community mentions are a useful proxy for real-world trust - people don't recommend brands they've had bad experiences with.
Side-by-Side Comparison
| Feature | CORE SARMs | Wartorn | Receptorchem | UKSARMs | Thoroughbred |
|---|---|---|---|---|---|
| Overall Score | 9.5/10 Best | 8.6/10 | 7.4/10 | 6.5/10 | 6.1/10 |
| Price | £45.00 | £39.95 | £49.99 | £59.99 | £44.99 |
| Format | Capsules | Capsules | Liquid | Liquid | Capsules |
| Dose / Unit | 10mg | 12.5mg | 25mg/ml | — | 12.5mg |
| Tested Purity | 99.2%+ | 99.38% | >99% | Verified | Not listed |
| Named Testing Lab | ✓ Janoshik | ✗ Not named | ✗ Not named | ✗ Not named | ✗ Not named |
| COA Available | ✓ Batch-specific | ✓ | ✓ HPLC | ✓ | Referenced |
| Absorption Enhancer | ✓ Piperine | ✗ | ✗ | ✗ | ✗ |
| ISO 7 Cleanroom | ✓ | ✗ | ✗ | ✗ | ✗ |
| GMP Facility | ✓ | ✓ | ✗ | ✗ | ✗ |
| Customer Reviews | 147 (4.86★) | 142 (4.92★) | Minimal | Not visible | None |
| Reddit Presence | High | Low | Medium | Low | None |
| UK Shipping | Free over £90 | Free over £75 | Paid | Paid | Paid |
Frequently Asked Questions
Our #1 Pick: CORE SARMs
Named lab testing. ISO 7 cleanrooms. The only MK-677 in the UK with piperine for enhanced absorption. 147 reviews. £45.
Visit CORE SARMs →