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Optimum NutritionSports & performance

Gold Standard 100% Casein Protein Powder 924 g (28 servings) Cookies & Cream

£45.00 for 924 g at Optimum Nutrition. That works out at £1.67 per 25 g protein, which ranks it 15th of the 17 casein protein products we price across 3 UK retailers.

What it really costs, per 25 g protein£1.67One 25 g dose is our comparison unit for protein powder. It is not a recommendation.
A day£1.67
A week£11.72
A month£50.22
A year£611.05

At one 25 g dose a day, this pack lasts 27 days. A month is 30 days, so twelve of them is not quite a year.

How we worked it out

  • Servings: 924 ÷ 33 per serving = 28
  • In the pack: 28 × 24 g = 672 g
  • £45.00 ÷ 672 g × 25 g = £1.67 per 25 g protein
  • A week £1.67 × 7 = £11.72 · a month × 30 = £50.22 · a year × 365 = £611.05
  • Amount per serving: stated on the label.

The standard dose is a comparison unit, not a recommendation. Always confirm the price on the retailer's site. How we compare everything.

Cheaper casein protein

All 17, ranked →
Impact Micellar Casein PowderMyprotein · 23 g a serving · £31.51 a month · a pack lasts 28 days£1.05£28.99View at Myprotein (opens in a new tab)
Impact Micellar Casein PowderMyprotein · 23 g a serving · £31.51 a month · a pack lasts 28 days£1.05£28.99View at Myprotein (opens in a new tab)
Gold Standard 100% Casein Protein Powder 924 g (28 servings) Creamy VanillaOptimum Nutrition · 24 g a serving · £50.22 a month · a pack lasts 27 days£1.67£45.00View at Optimum Nutrition (opens in a new tab)
This productOptimum Nutrition · 24 g a serving · £50.22 a month · a pack lasts 27 days£1.67shown above

Switching to the Myprotein pack saves £18.71 a month at the same 25 g dose.

Ranked purely by price per 25 g protein.

On the label

Protein powder · Casein
24 g per serving (stated on the label)
Pack
924 g · 28 servings · 33 g a serving
Cost per serving
£1.61 (28 servings in the pack)
More label details
Sold by
Optimum Nutrition
What the listing says
“Cookies & Cream” · “924 g” · “(28 servings)” · “33 g” · “Protein ; 74 g ; 24 g”
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One 25 g dose is our comparison unit, not a recommendation.

Price history

No price change since 23 September 2026. Checked on 2 days, most recently 9 October 2026.

Price at every check
£45.00Optimum Nutrition
First recorded
£45.0023 Sept
Checked on
2 dayssince 23 Sept
Pack price at each check.
  1. First checked at Optimum Nutrition: £45.00

Questions about this product

How much does Optimum Nutrition Gold Standard 100% Casein Protein Powder 924 g (28 servings) Cookies & Cream cost per 25 g protein?

£1.67 per 25 g protein, from £45.00 for 924 g at Optimum Nutrition, checked on 9 October 2026.

Is it the cheapest casein protein in the UK?

No, it is 15th of 17. Impact Micellar Casein Powder at Myprotein works out at 91p per 25 g protein.

How long does one pack last?

27 days at one 25 g dose. The pack holds 672 g in total.

About Optimum Nutrition

Founded 1986 · Downers Grove, Illinois, United States · Part of Glanbia

Optimum Nutrition is a US sports nutrition brand founded in 1986 and headquartered in Downers Grove, Illinois. It has been owned since 2008 by Glanbia plc, an Irish nutrition group. It sells protein powders, including Gold Standard 100% Whey, as well as clear protein, creatine, pre-workout, electrolytes, collagen and vitamins.

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