CHEAPEST
19.8g
89
0.8g
0.3g
Casein
Cheapest Casein Protein UK
Compare casein products by cost per 25g protein.
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Size
1kg
20g
89
1.1g
0.5g
Size
1.8kg
21.2g
89
1g
0.5g
Choose size
19.5g
88
1.7g
0.5g
Size
1kg
20.5g
95
1.3g
0.9g
Choose size
19.2g
88
1.7g
0.8g
Size
1kg
20.2g
88
1.4g
0.3g
Size
1.588kg
18.8g
91
2.8g
0.5g
Size
900g
21.2g
88
1g
0.5g
Choose size
20g
93
1g
0.5g
Size
900g
20.5g
88
0.5g
0.4g
Size
1.5kg
17.5g
86
2.7g
0.6g
Choose size
20g
94
1g
1g
Size
907g
20g
93
1.3g
0.8g
Choose size
18.5g
88
1.5g
0.6g
HIGHEST PROTEIN %
Size
907.18g
22.1g
81
2.2g
0g
Size
1kg
17.8g
87
2.5g
0.4g
Size
600g
21.2g
89
1g
0.5g
Size
900g
18.3g
91
2.5g
0.7g
Size
500g
20g
93
1g
0.8g
Size
300g
19.8g
91
0.9g
0.5g
Size
500g
17.8g
87
3g
0.2g
Browse All Casein Products (22)
About Casein Protein
Casein is a slow-digesting protein derived from milk, making it ideal for overnight recovery or as a between-meals protein source. It forms a gel in the stomach, providing a sustained release of amino acids over several hours - which is why many athletes take it before bed.
Compare every casein protein product available from UK retailers below, sorted by price per 100g. Casein typically costs more than whey concentrate but serves a different purpose in your nutrition plan.
If you are looking for a fast-absorbing post-workout option instead, whey concentrate or whey isolate would be more appropriate. For a plant-based slow-release alternative, look for casein-like blends in our vegan section.
Shop by goal
Pick a target, see the shortlist.
Brand battles
Two brands, one clear winner.
MyproteinBulk
The UK's two biggest DTC brands, head-to-head
ONMyprotein
Premium global vs budget UK favourite
MyproteinProtein 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. Every price is read from the retailer's own page and checked daily. 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
Real prices, checked daily
Prices come from the retailer's own listing, never an RRP, and we re-check them every day rather than leaving a feed to drift.
04
Rankings can't be bought
Rank order is cost per 25g of protein. Some outbound links earn commission, and some Amazon links marked Ad pay per click; none of them buy a position in the table.
Questions, answered.
Casein is most commonly taken before bed because it digests slowly over 6-8 hours, providing a sustained release of amino acids during sleep. It can also be used as a meal replacement or between meals.
Yes, casein is typically 20-40% more expensive than whey concentrate per 100g. Use the price comparison above to find the best value casein in the UK right now.