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Muscle Gain

Collection: Muscle Gain

Build size, strength and lean muscle with our premium muscle gain supplements at The Box Supplements. Whether you're looking for high-quality whey protein, mass gainers, creatine or intra-workout support, we stock trusted brands to help maximise muscle growth and recovery. Ideal for beginners and advanced lifters alike, our muscle-building range is designed to support progressive overload, improved recovery and consistent results. Shop muscle gain supplements in the UK with fast delivery and outstanding customer service.

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1792 products

USN Muscle Fuel Anabolic 2kg - Cookies & Cream

USN Muscle Fuel Anabolic 2kg - Cookies & Cream

Regular price £35.99
Sale price £35.99 Regular price
USN Muscle Fuel Anabolic 2kg - Banana

USN Muscle Fuel Anabolic 2kg - Banana

Regular price £35.99
Sale price £35.99 Regular price
USN Blue Lab Whey 2kg - Cookies & Cream

USN Blue Lab Whey 2kg - Cookies & Cream

Regular price £59.99
Sale price £59.99 Regular price
USN Blue Lab Whey 2kg - Caramel Chocolate

USN Blue Lab Whey 2kg - Caramel Chocolate

Regular price £59.99
Sale price £59.99 Regular price
USN Blue Lab Whey 2kg - Chocolate

USN Blue Lab Whey 2kg - Chocolate

Regular price £59.99
Sale price £59.99 Regular price
Per4m Advanced Whey Protein 2.01kg - Apple Strudel

Per4m Advanced Whey Protein 2.01kg - Apple Strudel

Regular price £55.99
Sale price £55.99 Regular price
Per4m Advanced Whey Protein 2.01kg - Salted Caramel

Per4m Advanced Whey Protein 2.01kg - Salted Caramel

Regular price £55.99
Sale price £55.99 Regular price
Per4m Advanced Whey Protein 2.01kg - Chocotella

Per4m Advanced Whey Protein 2.01kg - Chocotella

Regular price £55.99
Sale price £55.99 Regular price
Per4m Advanced Whey Protein 2.01kg - Chocolate Brownie Batter

Per4m Advanced Whey Protein 2.01kg - Chocolate Brownie Batter

Regular price £55.99
Sale price £55.99 Regular price
Optimum Nutrition Platinum Hydro Whey 1.6kg - Chocolate

Optimum Nutrition Platinum Hydro Whey 1.6kg - Chocolate

Regular price £98.99
Sale price £98.99 Regular price
Optimum Nutrition Gold Standard 100% Whey 4.54kg - Vanilla Ice Cream

Optimum Nutrition Gold Standard 100% Whey 4.54kg - Vanilla Ice Cream

Regular price £174.99
Sale price £174.99 Regular price
NutriSport H3avyweight Whey Protein Complex 3kg - Banana

NutriSport H3avyweight Whey Protein Complex 3kg - Banana

Regular price £42.99
Sale price £42.99 Regular price
NutriSport 90+ Protein 5kg - Strawberry

NutriSport 90+ Protein 5kg - Strawberry

Regular price £59.99
Sale price £59.99 Regular price
NutriSport 90+ Protein 2.5kg - Vanilla

NutriSport 90+ Protein 2.5kg - Vanilla

Regular price £35.99
Sale price £35.99 Regular price
NutriSport 90+ Protein 2.5kg - Strawberry

NutriSport 90+ Protein 2.5kg - Strawberry

Regular price £35.99
Sale price £35.99 Regular price
NutriSport 90+ Protein 2.5kg - Banana

NutriSport 90+ Protein 2.5kg - Banana

Regular price £35.99
Sale price £35.99 Regular price
MyProtein Impact Casein 2.5kg - Vanilla

MyProtein Impact Casein 2.5kg - Vanilla

Regular price £48.99
Sale price £48.99 Regular price
MyProtein Impact Casein 2.5kg - Chocolate

MyProtein Impact Casein 2.5kg - Chocolate

Regular price £48.99
Sale price £48.99 Regular price
Mutant Whey Dual Chamber 1.8kg - Triple Chocolate & Vanilla Ice Cream

Mutant Whey Dual Chamber 1.8kg - Triple Chocolate & Vanilla Ice Cream

Regular price £46.99
Sale price £46.99 Regular price
Ghost Whey Protein 924g Peanut Butter Cereal Milk

Ghost Whey Protein 924g Peanut Butter Cereal Milk

Regular price £42.99
Sale price £42.99 Regular price

FAQ's

How long will delivery take?

We ship via DPD Next Working Day for orders placed before 3pm. Please allow 1 working day for order handling and dispatch, plus 1 working day transit.

How long do I have to return an item?

You have 30 days from the date you receive your order to return any items.

What happens if I order after the 3pm cut-off?

Orders placed after 3pm will enter our handling queue the next working day, and you’ll then need 1 working day for processing plus the usual 1 working day for DPD delivery.

How do I start a return?

Simply fill out the Customer Returns Form and we’ll send you the return instructions.