How Much Should Protein Powder Cost in the UK?
What counts as cheap, fair and overpriced for protein powder in the UK, in pounds per kilogram and per 25g of protein. Plus why the per-kilogram figure everyone quotes is the wrong one to judge on.
Kevin, founder of WheyWise
Plant protein well under the benchmark
Protein Works
Vegan Soy Protein Black
1kg bag
Buy Vegan Soy Protein Black →Direct from Protein WorksQuick answer
The typical whey concentrate in the UK costs £1.16 per 25g of protein. That is the median across 106 in-stock products we track, and the middle half of them sit between 94p and £1.39. Aim to pay under 94p, which puts you in the cheapest quarter of the market. The simplest yardstick is Myprotein Impact Whey at 96p per 25g of protein in the 2.5kg bag on Amazon: if you are paying much more than that for a plain whey, you should be able to say what the extra buys. If you would rather go plant-based, Protein Works Vegan Soy Protein BLACK is 36p. Judge on cost per 25g of protein rather than price per kilogram, because protein density runs from 56g to 90g per 100g across the products in this guide.
How much should you pay for protein powder?
The typical whey concentrate in the UK costs £1.16 per 25g of protein, and the middle half of the market costs 94p to £1.39. Pay under 94p and you are in the cheapest quarter. That is the benchmark, built from the cheapest in-stock pack of each of 106 whey concentrates we track, and everything below explains where its edges are.
The spread around it is larger than most people expect. The cheapest product filed under whey concentrate in our tracking works out at about 32p per 25g of protein, though it is a whey, casein, soy and wheat blend, and the dearest at over £4, so the cheapest quarter and the dearest quarter of the market are a long way apart for products that do the same job.
What counts as cheap, fair and overpriced per kg
People search in pounds per kilogram, so here is the honest version in those terms, with the caveat that follows in the next section. The typical whey concentrate costs £33.22 per kilogram, and the middle half cost £27.32 to £41.00.
| Band | Price per kg | Whey concentrates here | What sits here |
|---|---|---|---|
| Exceptional | Under £20 | 10 of 106 | Big bags and entry lines. Check the label: Bulk Basic Whey is £13.20 per kg but carries 56g of protein per 100g from whey and soy. |
| Good value | £20 to £27 | 17 of 106 | The rest of the cheapest quarter. Applied Nutrition Critical Whey is £26.84 per kg in the 2kg bag on Amazon. |
| Fair | £27 to £41 | 52 of 106 | The middle half of the market. Myprotein Impact Whey is £27.60 per kg in the 2.5kg bag and Optimum Nutrition Gold Standard £37.48 in the 4.5kg tub. |
| Premium | Over £41 | 27 of 106 | Small tubs and specialist lines such as grass-fed and organic wheys. |
Price per kilogram of the cheapest in-stock pack of each active whey concentrate we track, from 200g up, using prices recorded in the ten days before this update. Products without a plausible protein per 100g figure left out.
Why price per kilogram is the wrong number
A kilogram of protein powder is not a kilogram of protein. Across the products in this guide, protein per 100g runs from 56g for Bulk Basic Whey and 59g for Protein Works Whey Protein 360 BLACK to 90g for PSN Soy Protein Isolate. So a kilogram of one product can contain more than half as much protein again as a kilogram of another at the same shelf price.
Worked example from current prices. Bulk Basic Whey is £13.20 per kilogram in the 2.5kg bag on Amazon, at 56g of protein per 100g. NutriSport Whey Protein Isolate is £14.00 per kilogram in the 5kg bag on Amazon, at 76.5g. On price per kilogram the Bulk bag is 6% cheaper. On cost per 25g of protein they are 59p and 46p, so the Bulk bag is 29% dearer. The cheaper-looking bag is the more expensive protein.
This is not a subtlety, it is the whole game, and it is also the position the most upvoted comments in UK protein threads take. The recurring top-voted advice is to check the protein per 100g and aim for 80g as a minimum rather than chasing the lowest sticker price, on the reasoning that some of the really cheap products are cheap for a reason.
One more trap in the same family: judge per 25g of protein, not per scoop. A brand can leave the advertised protein per serving unchanged while reducing protein per 100g, simply by making the scoop bigger. The front of the bag reads the same and every kilogram you buy contains less protein.
The bands that actually matter, per 25g of protein
The median whey concentrate costs £1.16 per 25g of protein, the median isolate £1.56 and the median vegan protein £1.05. These bands are for whey concentrate, the powder most people buy.
| Cost per 25g protein | Verdict | Whey concentrates here | Cost per month, one shake a day |
|---|---|---|---|
| Under 60p | Exceptional, check what it is | 7 of 106 | Under £18 |
| 60p to 94p | Good value, the cheapest quarter | 20 of 106 | £18 to £28 |
| 94p to £1.39 | Fair, the middle half | 52 of 106 | £28 to £42 |
| £1.39 to £2 | Premium | 19 of 106 | £42 to £60 |
| Over £2 | You are paying for the name or the format | 8 of 106 | Over £60 |
Monthly figures assume one 25g-of-protein serving a day for 30 days.
| Type | Products counted | Median per 25g protein | Middle half of the market |
|---|---|---|---|
| Whey concentrate | 106 | £1.16 | 94p to £1.39 |
| Whey isolate | 34 | £1.56 | £1.25 to £1.69 |
| Vegan protein | 86 | £1.05 | 57p to £1.69 |
| Clear whey | 29 | £1.76 | £1.50 to £2.21 |
Cost per 25g of protein for the cheapest in-stock pack of each active product we track, from 200g up, using prices recorded in the ten days before this update. The middle half runs from the 25th to the 75th percentile. Products without a plausible protein per 100g figure were left out: three whey concentrates, one isolate and five vegan products.
The monthly column is the one worth internalising. Moving from the top of the cheapest quarter to the top of the middle half costs about £13.50 a month. Moving from 94p to £2 costs about £32 a month, or close to £380 a year, for a product that in protein terms is broadly the same.
Vegan protein has the widest spread of the four, from 57p to £1.69 across its middle half, because 5kg bags of plain soy and pea isolate sit in the same category as small tubs of flavoured blends. Its cheapest quarter is cheaper than whey's, which surprises most people.
Under 60p: what a genuine bargain looks like
Pure Source Nutrition PSN Soy Protein Powder
2.5kg bag
The very bottom of the market done properly: a plain soy isolate at 90g of protein per 100g for about 22p per 25g of protein. Buy a small bag first if flavour matters to you.
Buy PSN Soy Protein Powder →See the price on AmazonUnder 60p: what a genuine bargain looks like
Pros
- + About 22p per 25g of protein in the 5kg bag on Amazon at £39.99
- + 90g of protein per 100g on Pure Source Nutrition's own label, the highest density in this guide
- + Soy protein isolate, a complete plant protein
Cons
- – Soy rather than whey, so the taste and texture differ from a whey shake
- – No large public review record to check flavour against before you buy
●Nutrition per scoop · 27g protein in 30g▼
Protein makes up 90%
of this 30g scoop · 114 kcal total
The benchmark
MyProtein Impact Whey Protein Powder
1kg bag
A yardstick rather than a bargain. If a plain whey concentrate costs much more than about 96p per 25g of protein, you should be able to say what the extra buys.
or compare all UK prices →The benchmark
Pros
- + 96p per 25g of protein in the 2.5kg bag on Amazon at £69, right on the edge of the cheapest quarter of the market
- + About 72g of protein per 100g
- + A very wide flavour range, so you can find one you will finish
Cons
- – Myprotein prices each flavour and size separately on its own site, so check the per-gram figure on the bag you pick
- – A plain whey from a smaller brand can cost half as much per gram of protein
●Nutrition per scoop · 21.6g protein in 30g▼
Protein makes up 72%
of this 30g scoop · 113 kcal total
Why isolate costs more, and when it is worth it
The middle half of the isolates we track carry 80g to 88g of protein per 100g, against 68g to 76g for the middle half of concentrates, and isolate is filtered further to strip most of the lactose and fat. That extra processing is real, and it costs real money: European whey protein isolate rose about 59% between October 2025 and July 2026, on top of a base that was already higher than concentrate.
In UK retail terms, the middle half of the isolates we track cost £1.25 to £1.69 per 25g of protein, with a median of £1.56, against 94p to £1.39 and a median of £1.16 for concentrate. That is about 40p a serving more at the median. Worth it if you are lactose intolerant or cutting calories tightly. Not worth it otherwise: the protein does the same thing.
Clear whey sits above even that, at a median of £1.76 per 25g of protein, and it is worth being clear that what you are buying there is a format, not better protein. Ten of the 29 clear wheys we track cost more than £2 per 25g of protein.
Does buying a bigger bag actually save money?
Usually. Not always, and the exception is more common than you would think.
The usual pattern first. Optimum Nutrition Gold Standard 100% Whey costs £1.39 per 25g of protein in the 2.27kg tub on Amazon and £1.23 in the 4.5kg tub, so the bigger tub is about 11% cheaper per gram. Now the exception. On Myprotein's own site, Impact Whey Isolate in Chocolate Caramel cost £48.99 for 1kg and £217.49 for 4.05kg. Per gram, the big bag was about 10% dearer than the small one, in the same flavour from the same retailer.
So the rule is not "buy bigger", it is "check the per-gram figure on every size". That check takes ten seconds and it is the only way to catch this kind of inversion, which no shelf price will show you.
The other half of the bag-size question is whether you will finish it. A 5kg bag at a great per-gram price is a bad purchase if you abandon it after three weeks because you dislike the flavour. Buy 1kg of anything new.
What UK buyers say they refuse to pay
The community benchmark sits well below the market median. In UK frugal and fitness discussions through 2026, roughly £11 to £12 per kilogram is the figure people describe as acceptable, around £16 per kilogram gets treated as the tolerable high-street level, and £20 and above draws complaints. One buyer summarised it as being able to live with £11 per kilogram on a 5kg bag. On our data, only 10 of the 106 whey concentrates we track come in under £20 per kilogram.
Worth being careful about how much weight to put on any individual comment, because most of them are unvoted. What is clearly significant is the volume of the conversation: a thread titled "Wheyflation" on the biggest bodybuilding forum drew 351 upvotes and 139 comments in July 2026, which tells you the price change is being felt broadly even if any one price quoted in it is not verifiable.
The pattern in the top-voted replies is consistent, and it is worth repeating because it cuts against the direction most price articles push: the advice that rises is to check protein density and avoid the very cheapest, not to hunt the lowest number.
To see where any specific product sits against these bands, the cheapest protein powder comparison ranks everything by cost per 25g of protein, the protein comparison tool puts any two products side by side, and the protein finder narrows the field if you have not chosen a type yet. For why the benchmark moved in the first place, see what actually drives UK protein powder prices, and for which brands have moved their prices, see which protein brands put prices up in 2026.
Frequently asked questions
How much should protein powder cost per kg in the UK?
The typical whey concentrate we track costs £33.22 per kilogram of powder, and the middle half sit between £27.32 and £41.00 per kilogram. Under about £27 per kilogram puts you in the cheapest quarter of the market. Big bags go much lower, down to about £10 per kilogram, but check the label at that end: Bulk Basic Whey is £13.20 per kilogram and carries 56g of protein per 100g from a whey and soy blend.
What is a good price per serving for protein powder?
Judge it per 25g of protein rather than per scoop, because scoop sizes differ. The median whey concentrate costs £1.16 per 25g of protein and the middle half cost 94p to £1.39, so anything under 94p is good value. The cheapest whey we can verify is NutriSport Whey Protein Isolate at about 46p. Myprotein Impact Whey is 96p in the 2.5kg bag and Optimum Nutrition Gold Standard £1.23 in the 4.5kg tub.
Why is price per kilogram misleading for protein powder?
Because protein density varies enormously. Across the products in this guide it runs from 56g of protein per 100g for Bulk Basic Whey to 90g for PSN Soy Protein Isolate. Bulk Basic Whey is 6% cheaper per kilogram than NutriSport Whey Protein Isolate, but 29% dearer per 25g of protein. Cost per 25g of protein normalises this, which is why WheyWise ranks on it.
Is it cheaper to buy protein powder in a bigger bag?
Usually, but not always, so check rather than assume. On Myprotein's own site, Impact Whey Isolate in Chocolate Caramel cost £48.99 for 1kg and £217.49 for 4.05kg, which made the big bag about 10% dearer per gram. The usual pattern still holds elsewhere: Optimum Nutrition Gold Standard is £1.39 per 25g of protein in the 2.27kg tub and £1.23 in the 4.5kg tub on Amazon.
Has protein powder got more expensive in the UK?
Yes, and the driver is wholesale rather than retail. European whey protein concentrate rose about 120% between October 2025 and July 2026, and UK shelf prices followed with a lag. Since late August the shelf has been mixed rather than rising: of 219 protein products we compared, 59 rose by more than 3% and 44 fell. A price that looked fair in 2024 is not a useful benchmark now, which is why the bands in this article are rebuilt from current prices.
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