Best Vitamin D Supplement UK 2026: Tablets, Sprays and D3 + K2

Britain sits far enough north that between roughly October and March the sun never gets high enough for your skin to make vitamin D at all. That's the whole reason the NHS recommends everyone consider a daily supplement through autumn and winter, and why vitamin D is the one supplement with genuine population-level backing in this country rather than marketing behind it.

The choosing part is simpler than the shelves suggest. You want D3 rather than D2, a dose somewhere between 1000 IU and 4000 IU, and a format you'll actually take every day. Everything else is packaging. Here are six that do the job, with what each one is genuinely best for.

How much do you actually need?

The Scientific Advisory Committee on Nutrition set the UK reference nutrient intake at 10 micrograms a day, year round, for everyone aged 4 and over. That's 400 IU, and it's a floor rather than a target.

At the other end, the NHS puts the safe upper limit for adults at 100 micrograms, which converts to exactly 4000 IU. Every high strength product below lands on that number, which is not a coincidence. Take one of those and you're at the ceiling, so don't stack it with a multivitamin that also contains D.

On the D3 versus D2 question, a meta-analysis in the American Journal of Clinical Nutrition found D3 raises blood levels more effectively than D2, with the clearest advantage for large intermittent doses and a narrower gap for daily dosing. Buy D3 anyway; it costs the same.

1. Nu U Nutrition Vitamin D 1000 IU: Best Overall

A year's supply of 1000 IU softgels for under seven pounds, which works out at less than two pence a day. The dose is the sensible one for most adults: two and a half times the NHS reference intake, nowhere near the upper limit, and small enough that you can take it alongside a multivitamin without doing sums.

Softgels suspend the D3 in oil, which helps with absorption and makes them easy to swallow compared with the chalky tablets some brands sell. The bottle is a full 365 count, so you buy it once a year and stop thinking about it. Nu U is a UK company and the product is manufactured here.

The catch is that 1000 IU won't satisfy anyone who has been told by a GP to correct a genuine deficiency, where higher doses are usually prescribed. The softgels also contain gelatin, so vegans need the Omvits option further down.

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2. Vitabiotics Ultra Vitamin D 1000 IU: Best Budget

Vitabiotics is the closest thing British supplements have to a household name, and the Ultra Vitamin D tablets are the cheapest way into a recognisable brand. At around four pounds they undercut almost everything, and the tablets are small, vegetarian and easy to take.

You get a shorter supply than the year-long bottles, so the price per tablet is not quite as good as the headline suggests. Work out the cost per day before you assume it's the bargain. What you're paying for is a company with decades of UK manufacturing behind it and quality control most cheap white-label brands can't claim.

Worth grabbing if you want to try a daily habit before committing to a 365 tablet bottle, or if you prefer a tablet you can split.

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3. BetterYou Vitamin D 3000 IU Oral Spray: Best Oral Spray

BetterYou built its business on this format, and the logic behind it is sound: spray the D3 onto the inside of your cheek and it absorbs through the mucous membrane rather than passing through your stomach and gut. For anyone with coeliac disease, Crohn's, a history of bariatric surgery, or simply a lifelong hatred of swallowing pills, that matters.

Each spray delivers 3000 IU, which is a solid winter dose, and one 15ml bottle covers roughly 100 doses. It tastes faintly of peppermint. It's also the most expensive way to take vitamin D on this page by cost per dose, by a wide margin.

Is spray absorption genuinely better than a tablet taken with food? For most healthy people with a working gut, the practical difference is small. For the people listed above, it's the reason to buy. Buy it for the convenience and the absorption route, not because a tablet won't work.

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4. WeightWorld Vitamin D3 4000 IU: Best High Strength

Four hundred tablets at the maximum sensible daily dose, for under a tenner. If you've been told your levels are low, if you're dark skinned and living in northern Britain, or if you genuinely never see daylight between November and February, this is the strength that makes sense.

The tablets are small and easy to swallow, which is not a given at this dose. WeightWorld manufactures in the UK and the supply lasts well over a year at one a day.

Two honest caveats. At 4000 IU you're at the NHS upper limit, so this is a supplement to take on its own rather than alongside a multivitamin, a cod liver oil capsule and a fortified shake. And unless you have a reason to think you're deficient, more is not better; there's no evidence that pushing blood levels higher than normal does anything useful.

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5. Omvits Vegan Vitamin D3 4000 IU + K2: Best Vegan

Standard D3 comes from lanolin, the grease in sheep's wool, which rules it out for vegans. Omvits sources its D3 from lichen instead, and the resulting molecule is identical to the animal-derived version, so nothing is lost in the swap. The 100mcg of K2 as MK-7 alongside it is the form with the longest half-life in blood.

Ninety tablets gives you three months, and the whole thing is lanolin free, gelatin free and made in the UK. We've reviewed Omvits vegan omega 3 separately and found the same pattern: a small British brand doing plant-sourced versions of the standard supplements without much fuss.

Price per day is higher than the mass-market tablets, which is the usual vegan premium. If you take warfarin, the K2 content makes this one to discuss with your GP first.

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6. Nutrition Geeks Vitamin D3 4000 IU & K2 MK7: Best D3 and K2 Combination

A full year of D3 and K2 in one tablet for ten pounds, which is the cheapest way to get both. The 4000 IU and 100mcg pairing matches what most combination products use, and the tablets are coated and easy to swallow.

The reasoning behind combining them: vitamin D increases calcium absorption, and K2 activates the proteins that steer that calcium into bone. It's a plausible mechanism with a reasonable evidence base for bone health, though considerably less certain than the case for taking vitamin D by itself. Treat K2 as a sensible extra rather than the main event.

Same warning as above about the 4000 IU ceiling and about vitamin K antagonists. For everyone else, this is the best value combination product on Amazon UK right now.

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Tablet, softgel or spray?

Softgels suspend D3 in oil and go down easily, which is why they suit most people. Plain tablets cost less and take up less space in a cupboard, though the cheapest ones can be chalky. Sprays cost the most per dose and earn it only if swallowing pills is a genuine problem or your gut absorbs poorly.

Whichever you pick, take it with a meal that contains some fat. Vitamin D is fat soluble, and a capsule swallowed with black coffee at 6am is doing less for you than the same capsule taken with breakfast.

What to look for on the label

• D3, not D2. Cholecalciferol on the ingredients list is what you want. Ergocalciferol is D2 and is the weaker of the two.
• Dose in both IU and micrograms. UK labels use micrograms; most marketing uses IU. 25mcg is 1000 IU, and 100mcg is 4000 IU.
• A UK or EU manufacturer. Supplements are regulated as food rather than medicine, so the manufacturer's standards matter more than the branding.
• Nothing else you don't need. Vitamin D plus a carrier oil is all a supplement needs. Long ingredient lists usually mean a proprietary blend at doses too small to matter.

If you're building out a supplement shelf around your training, our guides to the best magnesium supplements and the best omega 3 cover the two other things worth taking year round for most people. The rest of our nutrition section has protein, creatine and everything else.

Recommended reads

1. The best magnesium supplements in the UK
2. The best omega 3 supplements in the UK
3. Omvits vegan omega 3 review
4. The best creatine in the UK
5. Vegan supplements for joints