Various · 2.5kg
19g
97
0.7g
1.8g
£0.41per 25g protein
£30.99 bag·1 retailer·
ON vs Myprotein
Optimum Nutrition vs Myprotein: Price Comparison 2026
Optimum Nutrition vs Myprotein head-to-head across every product, ranked by cost per 25g protein. UK pricing across both brands, each price shown with its check date.
54 products tracked57+ retailersDated price checks
Back to all proteinQuick filters
CHEAPEST
Vegan2.5kg
Chocolate Smooth · 5kg
21g
90
0.4g
0.2g
£0.41per 25g protein
£69.49 bag·1 retailer·
HIGHEST PROTEIN %
Vegan5kg
Banana · 2.5kg
17.5g
90
0.8g
0.8g
£0.51per 25g protein
£35.99 bag·1 retailer·
Vegan2.5kg
Chocolate Salted Caramel · 5kg
18g
98
1.7g
1.8g
£0.52per 25g protein
£75.49 bag·1 retailer·
Vegan5kg
Chocolate · 2.5kg
20g
93
1g
0.8g
£0.58per 25g protein
£46.49 bag·1 retailer·
CHEAPEST
Casein2.5kg
Vanilla · 2.5kg
16.3g
107
0.9g
4g
£0.62per 25g protein
£39.99 bag·1 retailer·
CHEAPEST
Whey concentrate2.5kg
Coconut · 5kg
16.3g
93
2.4g
1.6g
£0.69per 25g protein
£89.99 bag·1 retailer·
Whey concentrate5kg
Chocolate · 5kg
20.5g
89
0.8g
0.3g
£0.73per 25g protein
£120.49 bag·1 retailer·
HIGHEST PROTEIN %
Casein5kg
Mocha · 5kg
18g
96
2.2g
1.5g
£0.75per 25g protein
£108.49 bag·1 retailer·
Whey concentrate5kg
Chocolate Smooth · 1kg
21g
90
0.4g
0.2g
£0.78per 25g protein
£26.12 bag·1 retailer·
Vegan1kg
Various · 4.54kg
19.8g
93
1.3g
1g
£0.84per 25g protein
£119.99 bag·1 retailer·
HIGHEST PROTEIN %
Whey concentrate4.54kg
Natural Chocolate (Informed Sport) · 1kg
18.5g
96
1.8g
1.5g
£0.84per 25g protein
£24.99 bag·1 retailer·
Whey concentrate1kg
Vanilla Flavour · 1kg
17.5g
90
0.8g
0.8g
£0.87per 25g protein
£24.47 bag·1 retailer·
Vegan1kg
Milk Chocolate · 2.1kg
18g
95
2.8g
1.1g
£0.91per 25g protein
£54.99 bag·1 retailer·
Whey concentrate2.1kg
Unflavoured · 2.5kg
19.5g
100
2g
1.4g
£0.96per 25g protein
£74.99 bag·1 retailer·
Whey concentrate2.5kg
Chocolate Flavour · 684g
19.8g
93
1.3g
1g
£0.97per 25g protein
£20.94 bag·1 retailer·
Vegan684g
Various · 899g
19g
94
1.3g
1.2g
£1.02per 25g protein
£27.99 bag·1 retailer·
Whey concentrate899g
Chocolate Orange From Fermentation · 1kg
19.8g
89
1g
0.5g
£1.03per 25g protein
£32.49 bag·1 retailer·
CHEAPEST
Whey isolate1kg
Double Chocolate · 684g
18.3g
100
1.7g
1.9g
£1.05per 25g protein
£20.94 bag·1 retailer·
Vegan684g
Vegan Protein Shake Powder · 684g
18.3g
100
1.7g
1.9g
£1.06per 25g protein
£21.12 bag·1 retailer·
Vegan684g
Various · 1kg
17.5g
90
0.8g
0.8g
£1.06per 25g protein
£29.68 bag·1 retailer·
Vegan1kg
Various · 2.27kg
19g
94
1.3g
1.2g
£1.12per 25g protein
£76.99 bag·1 retailer·
Whey concentrate2.27kg
Unflavoured · 1kg
19g
97
0.7g
1.8g
£1.12per 25g protein
£33.99 bag·1 retailer·
Vegan1kg
Brown Sugar Milk Tea · 2.5kg
7.3g
97
12.8g
1.4g
£1.15per 25g protein
£33.49 bag·1 retailer·
BULK GAINS
Mass gainer2.5kg
Browse All ON & Myprotein Products (54)
Optimum Nutrition vs Myprotein: The Breakdown
Optimum Nutrition and Myprotein are two of the most popular protein brands in the UK, but they target different ends of the market. Optimum Nutrition (ON) is best known for Gold Standard Whey - a gym staple sold across dozens of third-party retailers. Myprotein sells direct and relies on frequent sales and discount codes to undercut on price.
This page compares every product from both brands side by side using UK pricing, normalised to cost per 25g of protein. Because ON products are stocked by many retailers, you will often see the same product at different prices - the grid shows the cheapest available option for each.
Every price is shown with the date it was checked. Myprotein tends to be cheaper on paper, but ON's pricing is more stable and you rarely need a discount code. Use the grid below to see which brand offers better value right now.
Shop by goal
Pick a target, see the shortlist.
Brand battles
Two brands, one clear winner.
Myprotein vs Bulk
The UK's two biggest DTC brands, head-to-head
ON vs Myprotein
Premium global vs budget UK favourite
Myprotein vs Protein Works
Impact Whey vs Whey 80, cheapest per 25g
Power users
Advanced comparison: every product, filteredDense table view with every product, full filter sidebar, and no editorial surfaces.
Methodology
How we rank every bag.
Independent and transparent, with every price shown alongside the date it was checked. Here's what goes into each score.
01
Cost normalised to £/25g
Every bag divided by its true protein weight, so you see the real cost of a scoop across any size or brand.
02
Protein density, measured
Protein per 100g from the product's own nutrition panel, so a 90% isolate and a 72% concentrate are never compared on bag price alone.
03
Every price carries its date
Prices come from the retailer's own listing, never an RRP, and each one is shown with the day it was last checked so you can judge how current it is.
04
No sponsored placements
Rank order is cost per 25g of protein. Some outbound links earn commission; none of them buy a position in the table.
Questions, answered.
Optimum Nutrition Gold Standard Whey consistently tests close to its label claims and uses whey isolate as the primary ingredient. Myprotein Impact Whey is a concentrate-first blend that delivers solid protein content at a lower price point. Both are reputable - ON is generally considered the premium option, while Myprotein wins on value.
ON uses whey isolate as the first ingredient in Gold Standard, sources from established US manufacturing, and sells through third-party retailers who each add margin. Myprotein manufactures and sells direct, cutting out the middleman. The price gap reflects distribution model as much as ingredient quality.
Prices vary significantly across retailers. Use the comparison grid above to find the cheapest price - we track ON products across 57+ UK retailers and show every price with the date it was checked.
54 results