Kirkland Signature (Costco)

Whey Protein

Running these analyses costs money. Buy through my links to help keep lights on! I may get a small commission.

Kirkland Signature (Costco) Whey Protein
TL;DR: Budget king; good quality for the price.

Overall

#3 in

Protein Powder

according to Reddit Icon Reddit

User sentiment70% positive
289
46
76
Last updated: Apr 9, 2026

Reddit Reviews

Reddit Icon1chester555 1.0
r/CostcoCanadaAny good?
26 days ago

I added a scoop of the vanilla one to my brownies and a scoop to my banana chocolate chip muffins. It’s improved the taste and added protein to my homemade goodies. Love it.

Reddit Icon2JZMX83 1.0
r/CostcoIs Kirkland protein powder decent? Or does the Optimum Nutrition brand taste better?
about 1 month ago

I didn't like it, upset my stomach. I stick with ON

Reddit Icon3BallCornerPocket 1.0
r/CostcoCanadaCalling all gym rats! How’s this protein?
2 months ago

Get Kirkland if you have it. Close enough and cheaper.

Reddit Icon4-snizzle-dizzle 1.0
Reddit Icon802ScubaF1sh 1.0
r/workoutThe Best Protein Powder at the Moment?
8 months ago

Our Costco almost always has the Kirkland, ON, and Orgain plant powders for a great deal. Look for the 'Aussie Bites' in the snack section, the ingredients / protein is pretty crazy for the small bites.

Reddit Icon89ShelbyCSX 1.0
r/CostcoWhat’s your favorite protein powder from Costco and why?
8 months ago

I find Kirkland to be over the top for me. Doesn't mix as well so you have to mix with more water and drink more of it. The cream flavor is really strong and very artificial and I personally dislike that enough to stick with ON

Reddit Icona7stringkilla 1.0
r/workoutThe Best Protein Powder at the Moment?
8 months ago

I agree. Kirkland whey protein is an unbeatable deal. Second would be whatever protein Grocery Outlet has at the moment.

Reddit IconA_90s_Reference 1.0
r/CostcoHow’s the Kirkland protein powder?
8 months ago

Chocolate milk kinda taste. It's great, especially when considering the price. It's the only thing I buy unless ON is on a great sale

Reddit Iconaaglancy 1.0
r/CostcoIs Kirkland protein powder decent? Or does the Optimum Nutrition brand taste better?
30 days ago

Costco brand messes my stomach up every time. Optimum Nutrition does not

Reddit IconAcceptable-Book 1.0
r/CostcoHow’s the Kirkland protein powder?
8 months ago

I switched to this one and am happy with it.