CHEAPEST
Choose size
22.5g
92
0.4g
0.4g
Cheapest protein
Cheapest Protein Powder UK
Compare protein powders by cost per 25g protein.
Quick filters
Choose size
21.5g
101
0.2g
2.2g
HIGHEST PROTEIN %
Size
5kg
22.8g
93
0.3g
0.5g
Size
5kg
17.5g
93
1.5g
1.3g
Choose size
21g
90
1.2g
0.3g
Choose size
17.8g
98
2.3g
1.9g
Choose size
19g
99
2g
1.4g
Size
1kg
20.9g
101
2.6g
1.9g
Size
1kg
20.9g
101
2.6g
1.9g
CHEAPEST
Size
5kg
18g
95
3g
1g
Choose size
22.5g
102
1.1g
0.7g
Size
4kg
18g
95
2.5g
1.3g
Choose size
20.5g
89
1.4g
0.3g
Choose size
21g
89
0.7g
0.2g
Choose size
21g
90
0.4g
0.2g
Choose size
19g
89
2.5g
0.4g
Choose size
19.5g
95
1g
1.4g
Choose size
19.8g
90
1.4g
0.7g
Size
1kg
20g
101
-
-
Choose size
20.3g
98
1.6g
1g
CHEAPEST
Size
5kg
19.1g
91
0.5g
0.3g
Choose size
20.8g
95
1.5g
0.6g
Choose size
19g
97
0.7g
1.8g
BULK GAINS
Choose size
11g
95
10.5g
0.7g
Browse All Products (321)
Finding the Cheapest Protein Powder in the UK
This page ranks every protein powder we track by the single metric that matters most: how much it costs to get 25g of protein. No marketing spin, no inflated RRPs - just the actual price you pay per serving of protein, normalised across different bag sizes, brands and retailers.
We include whey concentrate, whey isolate, casein, vegan and plant-based products. The cheapest option across all types floats to the top. Whether you are looking for cheap whey protein, an affordable isolate or a budget vegan blend, use the filters to narrow by category, brand or size.
We check prices across UK retailers including Myprotein, Bulk, Amazon UK, Holland & Barrett, Protein Works and more, and every price is read from the retailer’s own page and re-checked daily. Looking for the best value protein powder in the UK? The grid below makes it easy to compare inexpensive options side by side without visiting every retailer yourself.
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
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.
It changes depending on sales and discount codes. The grid above is sorted by cost per 25g of protein, so the product at the top is the cheapest across all UK retailers we track, and every price is read from the retailer’s own page and re-checked daily.
We take the price of the product, divide by the total grams in the bag, then multiply by how many grams you need to get 25g of actual protein (based on the product's protein percentage). This gives a fair comparison regardless of bag size or serving suggestion.
Price and quality are not always correlated. The cheapest options are typically whey concentrate from large UK brands like Myprotein or Bulk - these are well-established products with consistent quality. Extremely cheap unfamiliar brands may be worth checking the protein content per 100g before buying.
The best budget protein powder depends on your needs. For pure value, whey concentrate from Myprotein or Bulk consistently ranks as the most affordable option per gram of protein. If you need low lactose on a budget, look for cheap whey isolate deals. For plant-based, Bulk's vegan blend tends to be one of the most inexpensive options.
Buy in larger bag sizes (2.5kg or 5kg) for a lower cost per serving. Use discount codes from retailers like Myprotein, Bulk and Protein Works. Compare prices per 25g of protein rather than per bag - a more expensive bag can actually be cheaper per serving. Our grid does this comparison for you automatically.