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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

Bio-Synergy Creatine Boost 1kg Orange

Bio-Synergy Creatine Boost 1kg Orange

Regular price £37.99
Sale price £37.99 Regular price
Bio-Synergy Active Woman Revitalise 450g Orange

Bio-Synergy Active Woman Revitalise 450g Orange

Regular price £24.99
Sale price £24.99 Regular price
Bio-Synergy Active Woman Activate 450g Strawberry

Bio-Synergy Active Woman Activate 450g Strawberry

Regular price £26.99
Sale price £26.99 Regular price
Bio-Synergy Active Woman Activate 450g Chocolate

Bio-Synergy Active Woman Activate 450g Chocolate

Regular price £26.99
Sale price £26.99 Regular price
Atlas Lean Mass MRP 1kg Banana & Malt

Atlas Lean Mass MRP 1kg Banana & Malt

Regular price £15.99
Sale price £15.99 Regular price
Applied Nutrition Creatine + Peptides 222g Unflavoured

Applied Nutrition Creatine + Peptides 222g Unflavoured

Regular price £21.99
Sale price £21.99 Regular price
Applied Nutrition Creatine + HMB 240g Unflavoured

Applied Nutrition Creatine + HMB 240g Unflavoured

Regular price £21.99
Sale price £21.99 Regular price
Animal Whey 2.27kg Caramel Latte

Animal Whey 2.27kg Caramel Latte

Regular price £75.99
Sale price £75.99 Regular price
Alpha Neon Creatine 1kg

Alpha Neon Creatine 1kg

Regular price £30.99
Sale price £30.99 Regular price
Applied Nutrition Iso-XP 850g White Choc Pistachio

Applied Nutrition Iso-XP 850g White Choc Pistachio

Regular price £40.99
Sale price £40.99 Regular price
Applied Nutrition Iso-XP 850g Cookies N Cream

Applied Nutrition Iso-XP 850g Cookies N Cream

Regular price £40.99
Sale price £40.99 Regular price
Applied Nutrition Iso-XP 850g Cafe Latte

Applied Nutrition Iso-XP 850g Cafe Latte

Regular price £40.99
Sale price £40.99 Regular price
Applied Nutrition Iso-XP 850g White Choco Hazelnut

Applied Nutrition Iso-XP 850g White Choco Hazelnut

Regular price £40.99
Sale price £40.99 Regular price
Applied Nutrition Creatine Gummies 80 Gummies Cherry Chill SLUSH PUPPiE

Applied Nutrition Creatine Gummies 80 Gummies Cherry Chill SLUSH PUPPiE

Regular price £17.99
Sale price £17.99 Regular price
Bio-Synergy Creatine Plus 375 Veg Caps

Bio-Synergy Creatine Plus 375 Veg Caps

Regular price £45.99
Sale price £45.99 Regular price
Bio-Synergy Creatine Boost Effervescent 20 Tabs Orange

Bio-Synergy Creatine Boost Effervescent 20 Tabs Orange

Regular price £14.99
Sale price £14.99 Regular price
Bio-Synergy Creatine Boost Effervescent 20 Tabs Berry

Bio-Synergy Creatine Boost Effervescent 20 Tabs Berry

Regular price £14.99
Sale price £14.99 Regular price
TWP ALL THE WHEY UP 900g Kandy Korn

TWP ALL THE WHEY UP 900g Kandy Korn

Regular price £33.99
Sale price £33.99 Regular price
Universal Nutrition Men's Total Health Pack 30 Packs

Universal Nutrition Men's Total Health Pack 30 Packs

Regular price £44.99
Sale price £44.99 Regular price
USN Whey Protein Bag 900g Chocolate

USN Whey Protein Bag 900g Chocolate

Regular price £29.99
Sale price £29.99 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.