The short answer (prices checked 21 October 2026)
- Cheapest day: EVO Nutrition Biotin Max, 400 tablets, 2.5p a day at the label's one-a-day serving.
- Cheapest biotin by weight: that same pack at 0.21p per 1,000 mcg. The dearest here is Solgar at 6.80p, about 33 times more for the same nutrient.
- Dearest day: Hair Burst gummies at 56.6p. Over a year the six packs on this page run £9.12 to £206.71.
- Biotin's nutrient reference value is 50 micrograms a day. Every pack here sells between 100 and 240 times that, so 100% of the reference intake costs about a hundredth of a penny.
- Audit finding: of the first 20 unsponsored Amazon UK results for "biotin" on 21 October 2026, 15 used growth or regrowth wording. None of biotin's seven authorised GB health claims mentions growth.
Biotin is having a moment on Amazon UK. When we read the Best Sellers charts on 21 October 2026, a pouch called Biotin Hair Growth Supplement sat at number 12 across the whole Health & Personal Care department and number one in the Biotin chart. Look at that subcategory chart and the pattern is hard to miss: the top eight slots were all biotin products sold on hair, and the headline doses ran from 5,000 mcg to 20,000 mcg.
Those numbers are the whole sales pitch. They are also where the interesting question lives, because the amount of biotin a pack contains and the thing a pack is allowed to promise you are set by two different pieces of law, and they point in opposite directions.
Prices in this table come from Amazon and are refreshed at least once a day, with the date of the last update under the table. The cost-per-use and running-cost figures on this page use prices Look Into read on 21 October 2026, so they can differ from today's price.
As an Amazon Associate, Look Into earns from qualifying purchases. Product prices and availability are accurate as of 21 October 2026 and are subject to change.
Prices and specs last checked by Look Into on 21 October 2026 · next check 16 December 2026 · how we picked
What a biotin label is allowed to say
Start with the reference intake. The nutrient reference value for biotin in Great Britain is 50 micrograms a day, set in Annex XIII of the retained Food Information to Consumers Regulation. A 12,000 mcg tablet is 240 times that figure. The number one best seller does the sum for you in its own bullet points, where it describes its 10,000 mcg as "20,000% NRV per serving".
Now the claims. Authorised health claims for nutrients sit in the Annex to retained Commission Regulation (EU) No 432/2012, and biotin has exactly seven of them. Four cover metabolism and the nervous system. The other three are the ones that sell packs:
- "Biotin contributes to the maintenance of normal hair"
- "Biotin contributes to the maintenance of normal skin"
- "Biotin contributes to the maintenance of normal mucous membranes"
Read that hair claim again. The authorised word is maintenance. There is no authorised GB claim that biotin grows hair, regrows hair, thickens hair or speeds hair up. And there is no authorised biotin claim for nails at all, which is awkward for a shelf where almost everything is branded "hair, skin and nails".
The nail wording has to come from somewhere else, and in the same Annex it does. Selenium carries two claims that matter here: "Selenium contributes to the maintenance of normal hair" and "Selenium contributes to the maintenance of normal nails". So on a pack that contains selenium, the nail sentence is doing legal work on 55 micrograms of selenium while the front of the pouch shouts about 12,000 micrograms of biotin.
One of the best sellers says so almost openly. New Leaf's listing explains that its formula "contains Zinc and Selenium as they both offer many health benefits, such as the maintenance of normal hair skin and nails", and then says biotin "is commonly taken to support healthy hair growth and nail health". The first half is the authorised claim attached to the right mineral. The second half is careful wording about what people do, not about what the nutrient is permitted to claim.
How we ranked them
Because the dose numbers are so large and so similar, a price tag tells you almost nothing on this shelf. We ranked on two figures instead, both worked out from the label's own serving and the buy-box price we read on 21 October 2026.
- Cost per day. Pack price divided by the number of days the pack lasts at the stated serving.
- Cost per 1,000 mcg of biotin. Cost per day divided by the thousands of micrograms in that serving. This is the figure that reorders the page.
The spread is the finding. Per day the six run from 2.5p to 56.6p, a factor of 23. Per 1,000 mcg of biotin they run from 0.21p to 6.80p, a factor of 33. Nothing about the nutrient changes across that range. What changes is pack size, format and brand.
How we picked these
We took the Amazon UK Biotin best sellers chart on 21 October 2026 and shortlisted six products with different jobs: the cheapest day, the cheapest year in one box, the chart leader, a smaller first pack, a high-street brand and a gummy. Every ASIN was opened and checked for price, stock and what the listing actually states. Where a listing does not give a figure we have said so rather than filled the gap. Look Into has not handled these products: every figure comes from the maker, the listing or a named source, read on the date shown.
How they compare
| Pick | Biotin per serving | Times the 50 mcg NRV | Pack | Cost per day | Per 1,000 mcg |
|---|---|---|---|---|---|
| EVO Nutrition Biotin Max | 12,000 mcg | 240x | 400 tablets | 2.5p | 0.21p |
| WeightWorld Biotin | 12,000 mcg | 240x | 365 tablets | 2.7p | 0.23p |
| Biotin Hair Growth Supplement | 10,000 mcg | 200x | 180 tablets | 3.9p | 0.39p |
| New Leaf Biotin | 12,000 mcg | 240x | 180 tablets | 5.0p | 0.41p |
| Solgar Biotin 5000 mcg | 5,000 mcg | 100x | 50 capsules | 34.0p | 6.80p |
| Hair Burst gummies | not stated | not stated | 30 day supply | 56.6p | cannot be worked out |
The six picks
EVO Nutrition Biotin Max with Zinc and Selenium
Four hundred tablets work out at 2.5p a day on the listing's one-tablet-a-day regime, and 0.21p per 1,000 mcg of biotin. It is the cheapest entry in both columns. It also carries zinc at 10 mg and selenium at 55 micrograms, which is the part of the formula the hair and nail wording can actually rest on.
The catch: 400 tablets is a thirteen month commitment before you know whether it suits you, and the listing describes the product as supporting "hair regrowth", which is not language any authorised biotin claim supports.
WeightWorld Biotin Tablets 12,000 mcg
Three hundred and sixty five micro tablets, one a day, 2.7p a day and 0.23p per 1,000 mcg. What sets this listing apart is the copy. It states the authorised claims word for word, including "Biotin contributes to the maintenance of normal hair", and leaves it there instead of promising growth. On a shelf where 15 of the top 20 reach for growth language, that is worth something.
The catch: there is no zinc or selenium in the pack, so nothing in it carries an authorised claim about nails, despite biotin's reputation as a nail supplement.
Biotin Hair Growth Supplement, 180 vegan tablets
This is the pack doing the volume. On 21 October 2026 it was number 12 in the whole Health & Personal Care department and number one in Biotin. It is the cheapest way onto this shelf, and at 3.9p a day it is still the third cheapest here. Biotin is 10,000 mcg, with zinc at 10 mg and selenium at 55 micrograms alongside it.
The catch: the listing puts "supports hair growth" directly next to the biotin figure. Biotin's authorised wording stops at maintenance, and at 180 tablets the per-day cost is more than half as much again as the 400 tablet pouch above.
New Leaf Biotin 12,000 mcg with Zinc and Selenium
A hundred and eighty tablets. Six months is a more sensible trial than thirteen, and the formula matches the pricier packs on paper. Its listing is also the clearest on this page about which nutrient does what, putting the hair, skin and nails wording on the zinc and selenium rather than on the biotin.
The catch: at 5.0p a day and 0.41p per 1,000 mcg it is the dearest of the 12,000 mcg tablets here, and the listing text never states the daily serving, so our figures assume the one tablet the title implies.
Solgar Biotin 5000 mcg, 50 vegetable capsules
Solgar is the name most people recognise on this shelf and the only pick here you will also find in health food shops. Fifty capsules at 5,000 mcg, one a day. Its dose is the most restrained of the six, which some buyers will read as a point in its favour given how far the rest have run.
The catch: the arithmetic is brutal. At 6.80p per 1,000 mcg it costs about 33 times what the cheapest pack here charges for the same nutrient, and 50 capsules is under two months. Its title also sells "Hair Growth" and "Strong Nails", neither of which biotin has an authorised claim for.
Hair Burst Hair Growth Biotin Gummies
If a tablet is the reason a supplement ends up unopened in a drawer, a chewable fixes that, and Hair Burst is the chart's established gummy. It sells as a 30 day supply.
The catch: the listing never states how much biotin is in a gummy, anywhere in the title, the bullet points or the product description, so the per-milligram column cannot be filled in for it at all. At 56.6p a day it is also the dearest pick on this page by a factor of 23 against the cheapest, and a year of it would come to £206.71.
What 20 biotin listings actually claim
On 21 October 2026 we read the first 20 unsponsored results on amazon.co.uk for the search term "biotin" and counted what each listing states. The scope was each product's own copy only: the listing title, the bullet points, the product description and the specification tables. Carousels of related products were excluded, because a page-wide search on Amazon will find almost any word you look for.
- All 20 state a biotin amount. The doses run from 5,000 mcg to 20,000 mcg, which is 100 to 400 times the 50 mcg reference value.
- 15 of 20 use growth or regrowth wording. Six of those never pair it with the authorised maintenance wording anywhere in the listing.
- 12 of 20 do use the authorised phrase "maintenance of normal hair" somewhere.
- 16 of 20 mention nails. Nine of those 16 contain neither zinc nor selenium, the minerals in this set that carry an authorised nail claim.
- Only 2 of 20 state the nutrient reference value. So on 18 of these listings the dose is the entire pitch and the yardstick that would make sense of it is absent.
That last count is the one we would hand a shopper. The headline number is the product, and nearly every listing leaves out the only figure that puts it in proportion.
Questions people ask
How much biotin does the law reckon you need a day?
Fifty micrograms. That is the nutrient reference value in Annex XIII of the retained Food Information to Consumers Regulation, and it is the figure the percentages on any pack are calculated against.
Can a biotin supplement say it makes your hair grow?
No authorised GB health claim for biotin mentions growth. The seven authorised claims cover metabolism, the nervous system, psychological function, skin, mucous membranes and the maintenance of normal hair. Growth language on a listing is marketing copy, not an authorised claim.
Why is everything branded hair, skin and nails if biotin has no nail claim?
Because the nail claim usually belongs to another ingredient. Selenium carries "contributes to the maintenance of normal nails" in the same Annex. On a pack containing selenium, that is where the nail sentence comes from. On a pack with no zinc and no selenium, which is nine of the 16 nail-mentioning listings we audited, it is harder to see what the wording rests on.
Is a 12,000 mcg tablet better than a 5,000 mcg one?
Nothing in the authorised claims distinguishes them. Both sit far above the 50 mcg reference value, and both support exactly the same seven claims. What the dose does change is the arithmetic: the 5,000 mcg capsule here costs 33 times more per 1,000 mcg than the 12,000 mcg tablet.
Does paying more get you more biotin?
Not on this shelf. The cheapest pack per day is also the cheapest per 1,000 mcg, and the two dearest per day are the 5,000 mcg capsule and the gummy that does not state its dose at all. Price here tracks pack size, format and brand.
Sources
- Annex to retained Commission Regulation (EU) No 432/2012, list of permitted health claims, read 21 October 2026, for biotin's seven authorised claims and the selenium hair and nail claims.
- Annex XIII, retained Regulation (EU) No 1169/2011, read 21 October 2026, for the 50 microgram nutrient reference value for biotin.
- Amazon.co.uk Best Sellers in Health & Personal Care and in Biotin, and the product listings for each ASIN named above, all read 21 October 2026.
Prices are the Amazon UK buy-box price read on 21 October 2026 and will have moved since. Look Into is an Amazon Associate and earns from qualifying purchases made through the links on this page, at no extra cost to you. Nothing here is medical advice; if you are considering a supplement because of hair loss, a pharmacist or GP is the right first stop.