Looking for the best mass gainer in Canada to fuel your bulk? You're in the right place. As Canada's largest-selection supplement retailer, we ship to every province plus the USA — and we've curated the most effective, highest-quality mass gainers available right now. This guide covers our four top in-stock picks, who each one is best for, and how to choose between them.
About Top Nutrition & Fitness: We're Canada's largest-selection supplement retailer based in Montreal, shipping coast-to-coast across Canada and to the USA — with no duties or tariffs added at checkout. With 1,000+ products across 200+ supplement and protein-snack brands, a 4.9/5 average on Google from 343 reviewers and 4.87/5 site rating from 565 verified customers, we curate the best of the supplement world — including hard-to-find brands you won't see at most Canadian retailers. Every order earns 5% cashback through our loyalty rewards program, and our rotating Mix & Match Snack Deal gives you Buy 5 Get 1 FREE on protein snacks.
Best Mass Gainers in Canada — Quick Comparison
| Mass Gainer | Brand | Size | Price | Best For |
|---|---|---|---|---|
| Mutant Mass | Mutant | 15 lbs | $129.99 | Hard-gainers needing 1,000+ cal surplus |
| Mammoth Mass 15lb | Mammoth | 15 lbs | $129.99 | Cleaner formula bulkers, easier digestion |
| Mutant Mass 5lb | Mutant | 5 lbs | $64.99 | First-time gainer users / trial size |
| Mammoth Mass 6lb | Mammoth | 6 lbs | $59.99 | Lean bulk, smaller portions |
1. Mutant Mass 15lb — Best Overall for Serious Bulking
Mutant Mass is the volume champion in our mass-gainer lineup. Each serving delivers approximately 1,100 calories with 56g of protein from a multi-source blend (whey concentrate, casein, milk protein concentrate) plus 224g of carbohydrates from oats, sweet potato and other complex sources. The 15-pound tub gives you about 14 servings — enough for 2 weeks of daily use at full dose, or 4+ weeks at half-scoop maintenance.
Best for: Hard-gainers, ectomorphs, athletes in calorie-deficit sports who need to recover fast. Skip if: you're already at maintenance or in a cut. Buy: Mutant Mass 15lb at Top Nutrition & Fitness — currently in stock.
2. Mammoth Mass 15lb — Cleaner Profile for Easier Digestion
Mammoth Mass takes a slightly different approach: fewer added ingredients, a focus on digestibility, and a smoother mixing texture that doesn't clump. The 15lb size matches Mutant on price ($129.99) but goes lighter on the calorie-dense extras. Great for users who get bloated on heavier gainers or who prefer a less-processed taste.
Best for: Sensitive stomachs, lean-bulk dieters, anyone prioritizing clean ingredients. Buy: Mammoth Mass 15lb.
3. Mutant Mass 5lb — Best Trial Size
Not sure if mass gainers are right for you? The Mutant Mass 5lb tub at $64.99 lets you try the formula before committing to the 15-pounder. Same flavor profile, same calorie-per-serving — just a smaller commitment. Plus you'll qualify for our free shipping if you stack with another item.
Best for: First-time gainer users, anyone testing tolerance. Buy: Mutant Mass 5lb.
4. Mammoth Mass 6lb — Lean Bulk Option
For lifters in a more controlled lean bulk (200-400 calorie surplus rather than 800+), the Mammoth Mass 6lb at $59.99 is the right pick. Smaller serving sizes, cleaner profile, easier to hit your macros without going overboard.
Best for: Lean bulkers, intermediate lifters refining body comp. Buy: Mammoth Mass 6lb.
How to Choose the Right Mass Gainer
Three questions answer this:
- What's your daily calorie goal? If you need 3,500+ calories and struggle with whole food, go with Mutant Mass 15lb (1,100 cal/serving). If you only need 200-500 surplus, Mammoth Mass 6lb is enough.
- How sensitive is your digestion? Heavier gainers can cause bloating. If that's been your experience, go Mammoth — it's cleaner and easier.
- How long is the budget cycle? 15-pound tubs are the better unit cost but require upfront investment. 5-6lb tubs work as starter sizes.
Why Buy Mass Gainers from Top Nutrition & Fitness
- National Canadian supplement retailer — we ship to every province plus the USA, with no duties or tariffs.
- Free shipping over $125 — most mass gainer orders qualify automatically.
- 5% cashback on every order through our loyalty rewards program — that's real cash back, not points that expire.
- Mix & Match Snack Deal — Buy 5 Get 1 FREE on protein snacks lets you stack a gainer with bars, drinks, and snacks for your whole bulking pantry.
- 4.9/5 Google rating from 343 reviewers, 4.87/5 site rating from 565 verified customers.
- Same-day shipping when you order before 1 PM ET (Mon–Fri).
- Hard-to-find brands and sizes Canadian competitors don't carry.
Frequently Asked Questions
Where can I buy mass gainers in Canada?
Top Nutrition & Fitness ships mass gainers from Mutant, Mammoth, PEScience and other top brands to all 10 Canadian provinces. We're a national supplement retailer based in Montreal with same-day shipping when you order before 1 PM ET, free shipping over $125, and 5% cashback rewards on every order.
What's the best mass gainer for skinny guys trying to bulk?
Mutant Mass 15lb is the most popular mass gainer in Canada for hard-gainers — it delivers 1,100 calories per serving with 56g of protein and 224g of carbs from a multi-source blend. It's calorie-dense and mixes easily for daily 1,000+ calorie surplus needs.
Mutant Mass vs Mammoth Mass — which is better?
Mutant Mass packs more calories per scoop (1,100 vs Mammoth's varies by serving size) and uses a multi-protein blend with whey, casein and milk protein concentrates. Mammoth Mass is slightly cleaner with fewer added ingredients and is easier on digestion for most users. We carry both — Mutant 15lb is the value pick at $129.99, Mammoth 15lb at $129.99 is the cleaner option.
How many calories should a mass gainer have?
Most effective mass gainers deliver 700-1,400 calories per serving. For lean bulking, look for 700-900 calories with a 2:1 carb-to-protein ratio. For hard-gainers needing serious surplus, 1,000+ calorie servings (like Mutant Mass) work better. Always pair with whole-food meals — gainers supplement, not replace.
Does Top Nutrition & Fitness ship mass gainers to the USA?
Yes — we ship to the entire United States with no duties or tariffs added at checkout. Free shipping qualifies on orders over $125 USD equivalent. Most US orders arrive in 5-7 business days.
Can I use a mass gainer instead of meals?
No. Mass gainers are designed to add calories on top of regular meals, not replace them. Whole foods provide micronutrients, fiber and digestive benefits that powder-based gainers can't match. Use 1 gainer shake per day in addition to 3-4 whole meals for best results.
What's the best Canadian-made mass gainer?
Mutant Mass and Mammoth Mass are both manufactured in Canada and are our top sellers among Canadian-made gainers. Both meet Health Canada NPN requirements and are produced in GMP-certified facilities.
