The strongest CBD oils in the UK in 2026 contain 500mg of CBD per ml: CBD Guru's 50% isolate oil and Honey Heaven's 5,000mg full-spectrum oil. We ranked 10 high-strength oils by CBD per ml, which is the only fair way to compare strength, and checked every price, extract type and lab report on 22 October 2026. Strength is not the only thing that matters, so we also picked the best oil for each need, from the strongest single-strain oil to the best everyday high-strength oil.
Key Takeaways
- The strongest CBD oil in the UK is 500mg per ml. CBD Guru's 50% oil and Honey Heaven's 5,000mg oil both reach it; no in-stock oil we found goes higher.
- Total mg on the label does not tell you how strong a CBD oil is. Orange County's 25,000mg oil is 250mg per ml because it comes in a 100ml bottle, half the strength of a 5,000mg oil in 10ml.
- The cheapest strong CBD oil per mg is an isolate. CBD Guru's 50% oil costs £0.53 per 100mg, but it contains CBD only, with none of the other cannabinoids or terpenes from the plant.
- Originals CBD Lemon Octane is the strongest single-strain CBD oil we found. It is cold-pressed from Lemon Octane hemp flower at 135mg per ml for £45, or £1.11 per 100mg.
- Strong CBD oil prices vary tenfold. Among the oils we ranked, prices run from £0.53 to £5.20 per 100mg, so compare price per 100mg, not price per bottle.
What Makes a CBD Oil Strong?
A CBD oil's strength is how much CBD it contains per ml, not the total mg on the front of the bottle. To work it out, divide the total CBD by the bottle size:
| Label | Bottle | CBD per ml | CBD per drop (approx.) |
|---|---|---|---|
| 3,000mg | 30ml | 100mg | 5mg |
| 4,050mg | 30ml | 135mg | 6.75mg |
| 6,000mg | 30ml | 200mg | 10mg |
| 25,000mg | 100ml | 250mg | 12.5mg |
| 5,000mg | 10ml | 500mg | 25mg |
Drop figures assume 20 drops per ml; real drop sizes vary, so use the brand's stated figure where there is one. A stronger oil is not a reason to take more CBD. It means each drop contains more, so you need fewer drops. The Food Standards Agency advises healthy adults to take no more than 10mg of CBD a day as a precaution. For how to measure a serving, see our guide on how to take CBD oil under your tongue.
How We Ranked the Strongest CBD Oils
This guide follows our editorial standards. We are a UK CBD retailer and two of our oils appear below, so we ranked on facts anyone can check, on 22 October 2026:
- Strength: CBD per ml, from each brand's own product page. Where a brand counts other cannabinoids in its headline figure, we used CBD alone.
- Availability: only oils in stock on the brand's UK website.
- Price: price per 100mg of CBD at the price shown on the day.
- Extract type: full spectrum, broad spectrum or isolate, as the brand states it.
- Lab reports: whether a certificate for the product is linked from its page.
Health claims made by brands played no part in the ranking.
The 10 Strongest CBD Oils in the UK, Ranked
| Rank | Oil | Strength | CBD per ml | £ per 100mg |
|---|---|---|---|---|
| 1 | CBD Guru 50% | 15,000mg / 30ml | 500mg | £0.53 |
| 1 | Honey Heaven 5,000mg Full Spectrum | 5,000mg / 10ml | 500mg | £2.70 |
| 3 | GreenLeaf 50% Signature (For the Ageless) | 4,000mg CBD / 10ml | 400mg | £4.63 |
| 3 | Naturecan 40% | 12,000mg / 30ml | 400mg | £1.92 |
| 5 | Biopurus 30% (For the Ageless) | 3,000mg / 10ml | 300mg | £5.20 |
| 6 | Orange County CBD 25,000mg | 25,000mg / 100ml | 250mg | £1.04 |
| 7 | Supreme CBD 24,000mg | 24,000mg / 100ml | 240mg | £0.83 |
| 7 | Provacan Ultimate 2,400mg | 2,400mg / 10ml | 240mg | £4.58 |
| 9 | Love Hemp 6,000mg | 6,000mg / 30ml | 200mg | £1.00 |
| 10 | Originals CBD Lemon Octane | 4,050mg / 30ml | 135mg | £1.11 |
| (for reference) | Originals CBD Natural Full Spectrum | 3,000mg / 30ml | 100mg | £1.67 |
| Oil | Extract type | Carrier oil | Price |
|---|---|---|---|
| CBD Guru 50% | Isolate | MCT | £79.99 |
| Honey Heaven 5,000mg | Full spectrum with added CBD distillate | Not stated | £135 |
| GreenLeaf 50% Signature | Full spectrum (plus 500mg CBG, 500mg CBC) | MCT (C8) | £185 |
| Naturecan 40% | Broad spectrum | Organic MCT | £229.99 |
| Biopurus 30% | Whole-plant full spectrum | Organic hemp seed | £155.90 |
| Orange County 25,000mg | Full spectrum | MCT | £260 |
| Supreme 24,000mg | Full spectrum | MCT | £199.99 |
| Provacan Ultimate | Full spectrum | Olive | £110 |
| Love Hemp 6,000mg | Broad spectrum | Not checked | £59.99 |
| Originals CBD Lemon Octane | Full spectrum, cold-pressed from one strain | Organic MCT | £45 |
The Best Strong CBD Oil for Each Need
1. Originals CBD Lemon Octane, strongest single-strain CBD oil
Most CBD oils, including every other oil on this list, are made from anonymous hemp extract. Lemon Octane CBD Oil is cold-pressed from one named strain, sungrown Lemon Octane hemp flower from Oregon, straight into organic MCT oil, with no solvents and no isolate. It is made with Improved Health, contains 135mg of CBD per ml (about 6.75mg per drop, or 4,050mg of CBD in the 30ml bottle) with CBG, CBC and CBN alongside. The 4,344mg on the label is the total of all cannabinoids, so we rank it on CBD alone, like every other oil here. It keeps the terpinolene and limonene profile of the flower, so it tastes of lemon rather than generic hemp.
At £45, it costs £1.11 per 100mg, cheaper per mg than every full-spectrum oil above it in the ranking except Supreme's and Orange County's 100ml bottles.
Best for: people who want a strong full-spectrum oil with a real strain profile, in a 30ml bottle at a fair price.
Trade-off: At 135mg per ml it is not the most concentrated oil here, and its lab certificate is available on request rather than linked on the page.
2. Originals CBD Full Spectrum Oils, best everyday high-strength oil
Originals' full-spectrum CBD oils are 3,000mg in 30ml (100mg per ml) for £49.99, in Natural, Mango, Strawberry, Black Cherry, Orange and Blueberry. Each drop gives a measured 5mg, which makes it easy to take exactly the amount you want. The Natural oil is tested by ISO 17025 and CDPHE-certified labs for cannabinoids, pesticides, residual solvents, heavy metals, mycotoxins and microbials. For zero THC, Mixed Berries is broad spectrum at the same price.
Best for: anyone who wants a strong 30ml oil they can measure precisely, with a full contaminant panel.
Trade-off: At 100mg per ml, it is a mid-to-high strength oil, not one of the most concentrated.
3. CBD Guru 50%, strongest CBD oil overall and cheapest per mg
CBD Guru's 50% oil holds 15,000mg of CBD in 30ml, or 500mg per ml, with 25mg per drop stated. At £79.99 (down from £99.99) it is £0.53 per 100mg, the lowest price per mg we found, and a certificate for the product is linked from its page. CBD Guru holds 4.2 on Trustpilot from 1,162 reviews.
Best for: people who want the most CBD per drop and per pound.
Trade-off: It is an isolate, so it contains CBD only, and at 25mg per drop small amounts are hard to measure.
4. Honey Heaven 5,000mg, strongest full-spectrum CBD oil
Honey Heaven's 5,000mg oil is full-spectrum extract combined with CBD distillate, at 500mg per ml in a 10ml bottle and about 27mg per drop according to the brand. It costs £135 (£2.70 per 100mg). At this concentration it can crystallise at room temperature, so you may need to warm the bottle before use. Honey Heaven holds 4.7 on Trustpilot from 122 reviews.
Best for: people who want the strongest oil that still contains other cannabinoids from the plant.
Trade-off: It is expensive per bottle, the carrier oil is not named on the page, and the lab page covers the whole site rather than this product.
5. Naturecan 40%, strongest broad-spectrum CBD oil
Naturecan's 40% oil is 400mg per ml in organic MCT oil, in 10ml (£129.99) or 30ml (£229.99, £1.92 per 100mg). It is broad spectrum, so it contains other cannabinoids but no THC. Naturecan holds 4.4 on Trustpilot from 4,696 reviews.
Best for: people who want a very strong oil with no THC from a large brand.
Trade-off: The certificate linked on the page is from a 2020 batch.
6. GreenLeaf 50% Signature (CBD Ultra 50% successor), strongest oil with added CBG and CBC
Sold by For the Ageless as the successor to CBD Ultra 50%, this 10ml oil contains 4,000mg of CBD plus 500mg of CBG and 500mg of CBC. That is 400mg of CBD per ml, or 500mg per ml counting all three cannabinoids, with 20mg of CBD per drop stated. A product certificate is linked, and For the Ageless holds 5.0 on Trustpilot from 979 reviews.
Best for: people who want a high-strength oil with meaningful amounts of other cannabinoids.
Trade-off: At £185 (£4.63 per 100mg) it is one of the most expensive oils per mg here.
7. Orange County CBD 25,000mg, best value large bottle
Orange County's 25,000mg oil is full spectrum in MCT oil, at 250mg per ml in a 100ml bottle, with 12.5mg per drop stated. It costs £260, which works out at £1.04 per 100mg. Orange County holds 4.8 on Trustpilot from 1,986 reviews. Note that its 12,000mg oil is also 100ml, so it is only 120mg per ml.
Best for: experienced users who want a large full-spectrum bottle at a low price per mg.
Trade-off: A high upfront cost, and the lab page covers the whole site.
8. Provacan Ultimate 2,400mg, best for a recent lab report
Provacan's Ultimate oil is full spectrum in olive oil, at 240mg per ml in a 10ml bottle for £110 (£4.58 per 100mg). Its product certificate is dated February 2026, the most recent we found among these oils. Provacan holds 4.4 on Trustpilot from 2,245 reviews.
Best for: people who want to see an up-to-date certificate before buying.
Trade-off: Expensive per mg.
Strong CBD Oil Pros and Cons
| Pros | Cons |
|---|---|
| Fewer drops for the same amount of CBD | Harder to measure small amounts |
| A bottle lasts longer | Higher price per bottle |
| Often cheaper per mg | The strongest and cheapest are often isolates |
| Useful if you already know the amount you take | Very concentrated oils can crystallise |
Frequently Asked Questions
What is the strongest CBD oil in the UK?
The strongest CBD oils in the UK contain 500mg of CBD per ml: CBD Guru's 50% oil (15,000mg in 30ml, isolate) and Honey Heaven's 5,000mg oil (5,000mg in 10ml, full spectrum). The strongest single-strain oil we found is Originals CBD Lemon Octane, at 135mg per ml.
Which CBD oil is the most potent?
Potency means CBD per ml. At 500mg per ml, CBD Guru 50% and Honey Heaven 5,000mg are the most potent CBD oils on sale in the UK that we found, followed by GreenLeaf 50% Signature and Naturecan 40% at 400mg per ml.
Is 5,000mg of CBD strong?
It depends on the bottle. A 5000mg CBD oil in a 10ml bottle is 500mg per ml, among the strongest oils in the UK. 5,000mg in a 30ml bottle is about 167mg per ml, a high but not exceptional strength.
Is 6,000mg of CBD strong?
6,000mg in a 30ml bottle is 200mg per ml, or about 10mg per drop, which is a high strength. 6,000mg in a 100ml bottle would be only 60mg per ml.
What is the strongest full-spectrum CBD oil in the UK?
Honey Heaven's 5,000mg oil, at 500mg per ml, is the strongest full-spectrum oil we found, though it has CBD distillate added. GreenLeaf 50% Signature is 400mg of CBD per ml plus CBG and CBC. Originals CBD Lemon Octane is the strongest oil we found cold-pressed from a single named strain.
What is the FSA's daily CBD advice?
The Food Standards Agency advises healthy adults to take no more than 10mg of CBD a day as a precaution, and says CBD is not recommended for under-18s, anyone pregnant or breastfeeding, or people taking medication unless under medical direction.
Try Originals CBD with 10% Off Your First Order
If you want a strong oil with a real strain profile, Lemon Octane is 135mg per ml for £45. If you want a measured everyday dose, our 3,000mg full-spectrum oils give 5mg per drop for £49.99. Weekday orders placed by 1pm are dispatched the same day. Sign up for 10% off your first order.
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CBD products are food supplements, not medicines, and are not intended to diagnose, treat, cure or prevent any disease. Not for under-18s, or for anyone pregnant or breastfeeding. Speak to your GP before use if you take medication. Strength figures are concentrations, not recommended servings. Competitor prices, strengths and ratings were checked on 22 October 2026 and may have changed.