I Spent 30 Days Testing Kirkland Whey Protein (Review)

As a budget-conscious shopper and a fan of Costco’s private-label products, I was curious when Kirkland introduced its own whey protein powder.   

I hoped it would offer great taste, mixability, quality ingredients, and affordability—without just being a repackaged, low-quality option. 

To my surprise, Kirkland’s whey protein delivered on most fronts, with impressive macros and a reasonable price.

However, a few factors could determine if it becomes a staple in your protein routine or not…

Key Takeaways

Honest Review Guarantee from FeastGood: Our testing team purchases each product 100% independently and uses the product for several weeks up to several months before writing a review. Learn more about our review process here.

• Kirkland Whey Protein is made with both isolate and concentrate and delivers 25g of protein per 130 calories. The protein-to-calorie ratio qualifies this whey protein as a “good” protein source per our FeastGood.com criteria of falling between 75-85% of protein per scoop.

• Kirkland Whey Protein costs $0.78 per serving (70 servings in the 5.4lb bag), placing it below the average cost of protein powders on the market, which we calculated to be $1.34 per serving.  

• There were some drawbacks, however, such as only one flavor offered, it is not third-party tested, and it did have added sucrose, oils, and emulsifiers.

About Kirkland (The Company)

The Costco brand, Kirkland Signature, is manufactured by name-brand third-party companies and offered exclusively to Costco members in stores. 

Some of the more notable Kirkland products that are made from established brands are:

• Starbucks Espresso Roast
• Bumble Bee Tuna
• Jelly Belly Candy
• Duracell Batteries
• Ocean Spray Cranberry Juice

While I’m unsure what third-party whey protein manufacturer is behind the Kirkland Whey Protein product, given the track record of the Kirkland Signature line, I can hypothesize that it is from a reputable company.

I have used many Kirkland products and foods before, such as their protein bars, meats, packaged foods, and even alcohol (whiskey, scotch, and wine), and I have always felt they were of high quality and value.

If you have tried Kirkland products before, you know what I mean, however, if you are new to the Kirkland line of products, you should know that Kirkland products are often name brands relabeled and provided to Costco members at an exclusive price.

Overall, I am a big fan of most Kirkland products.

Overview of Kirkland Whey Protein Powder

I specifically reviewed the Kirkland Whey Protein powder in the creamy chocolate flavor. It combines whey protein isolate and concentrate.

They include cocoa, acacia (soluble fiber used as a thickening agent), acesulfame potassium (artificial sweetener), sucralose (artificial sweetener), sea salt, oat bran (soluble fiber used as a thickening agent), and organic sunflower lecithin and oil (for thickening). 

They also have natural flavors, rice dextrin (adds texture), rosemary extract (helps degradation of product), and guar gum and xanthan gum (both used as thickeners).

The macronutrient breakdown is: 

• Calories: 130
• Protein: 25g  
• Carbohydrates: 4g
• Fat: 1.5g
• Sugar: 1g

Kirkland only offers their whey protein in one flavor: Creamy Chocolate.

The protein-to-calorie content of this protein is 76%, which places it at the lower end of the GOOD category for protein percentage.

As per Feastgood.com criteria, a “Reasonable” protein percentage is anything between 60 and 74% protein per scoop, with 75-85% being “Good,” and anything above 85% being considered “Excellent.”

Highlights: What I Liked About Kirkland Whey Protein

Price

Broken down by numbers, Kirkland is $0.78 per serving, whereas the average cost of protein is $1.34.  

The price is very reasonable, especially when it delivers quality macros and total protein. 

This, however, comes as no surprise, as I am very familiar with the high value and quality the Kirkland line delivers to Costco members.

Digestibility

I usually don’t have issues digesting whey protein powders, and this one was no exception. 

I appreciated that it includes acacia and oat fiber, which can have potential digestive benefits. 

Acacia, a soluble fiber, can help reduce gastrointestinal distress by forming a gel-like substance in the gut, aiding in smooth digestion. Oat fiber can promote regular bowel movements and support overall digestive health. 

While these fibers may have different effects based on individual tolerance, they can be beneficial for those looking for added digestive support. 

I found that the added fibers also gave the protein shake a pleasant, thicker texture, which I enjoyed.

Mixability and Taste

One of my favorite flavors of most whey protein powders is chocolate, as it mixes well with milk, water, and oats (add peanut butter, and it’s amazing).

This protein didn’t clump like other protein powders in the same price range, which is often hard to find. 

I mixed it mostly with water (at the gym after workouts) and milk (almond and whole milk), which had no issue mixing to create a smooth, clumpless texture.

The taste was rich and creamy, with a satisfying chocolate flavor, making it enjoyable to drink even on its own.

Drawbacks: What I Didn’t Like About Kirkland Whey Protein

Only One Flavor

Luckily for me, the only flavor that was offered happened to be the flavor (creamy chocolate) that I generally like to consume. My wife, however, likes to experiment with other flavors to add variety to her shakes, so this protein wasn’t suitable for her.

If you do not like chocolate powder, this is a huge miss. Kirkland is most likely trying to see how the product does by offering one of the most popular flavors. I wouldn’t be surprised if in the future, they expanded their line to include a vanilla or unflavored option.

Need a Costco Membership

You will only be able to get this if you or someone you know is a Costco member. This, of course, is the entire model of the Costco stores, so it comes with the territory. 

I definitely wouldn’t buy a Costco membership just to buy this protein powder. But, if you already shop at Costco, then it’s something to consider.  

Not Set Up for International Distribution

Currently, Costco only offers this protein within the United States. If you are a resident outside these countries, you likely will not have access to the Kirkland Whey Protein. 

And the fact that Costco products are not sold on any other platform (Amazon for example), if you are outside the United States, you are out of luck.

NOT Third-Party Tested

Third-party tested products are held to the highest standards of quality, as unbiased third parties verify their contents. However, this product is not third-party tested, which means we cannot be certain that everything on the label has been thoroughly tested and validated.

While I believe Kirkland is a high-quality brand, I cannot recommend this protein to elite athletes who are subject to drug testing. Although obtaining third-party quality assurance can be more expensive for brands, it is crucial to have this guarantee for complete trust in the product.

Many Unnecessary Additives

There are a lot of additives in the Kirkland protein, more than the average bottle of protein.  

Kirkland adds multiple artificial sweeteners (sucrose and acesulfame potassium) as well as multiple thickening agents a(guar gum, xantham gum, rice dextrin, and sunflower lecithin). 

The sweeteners do exactly what they are intended to (I found this to be a sweeter protein powder), and the emulsifiers gave it a thicker, creamier consistency. 

Granted, these additional ingredients don’t make it the most natural product, and many consumers, including myself, are choosing to avoid these additives altogether.  

How Does Kirkland Whey Protein Stack Up Against Our Criteria For Whey Protein

At FeastGood, we have eight key criteria for assessing whey protein powders.  Here’s how Kirkland Whey Protein stacked up:

Nutrition Label Transparency

Our rating: 3/5

The Kirkland label was clean and easy to read, as well as clearly displayed on their website.  However, without unbiased third-party testing to verify the bottle’s ingredients, multiple points were deducted. 

Fat Content Transparency 

Our rating: 4/5

Kirkland Whey Protein has 1.5g of total fat with no trans fat and 1g of saturated fat, clearly identified on the nutrition label. The 1g of saturated fat is not significant, however essential to point out because other high-quality whey proteins, like Transparent Labs, do not have saturated fat in them with the same flavors.

Effective Ingredients 

Our rating: 3/5

Kirkland Whey Protein is primarily from isolate, which is digested quicker and could be ideal for post workout. That said, it does also include concentrate which may slow absorption, which can be a concern if this is a high priority.

This product also has 3+ thickening agents and two artificial sweeteners, which may be excessive.  

Other protein powders have achieved the same level of sweetness and creaminess without as many additives.  

Protein Percent of Calories

Our rating: 3.5/5

Kirkland falls within the average protein percent of calories, being 76%.  This is a respectable amount of protein per serving, and if you find yourself with a protein powder with this percentage, you shouldn’t  be worried. 

Personally,  though, I’m willing to spend slightly more for a higher protein percentage product and look for brands that have at least 85% of calories coming from protein.  

Taste/flavor

Our rating: 4/5

Wow, I was impressed with the taste and flavor of this one. I have tried other whey proteins in this price range and have often felt they tasted chalky and bland. 

The only issue I had was that it could be too sweet at times, mostly due to the two artificial sweeteners.  It’s important to note that I’m also coming off testing protein powders that are minimally sweetened, so I might not be used to this level of sweetness yet.

That said, I’ve definitely had sweeter proteins powders, such as Quest, which tasted very sweet and artificial.

Mixability

Our rating: 5/5

Again, Kirkland nailed this one. 

I have had other whey proteins in this price range and found that there were STILL clumps no matter how vigorously I shook my shaker. I even used a spoon to mix it with water once (which realistically is THE WORST way to mix and drink any protein powder), and it clumped very minimally.

My shaker had minimal residue left over, but there was just some on the inside due to its thicker consistency.

Texture (Thick or Thin)

Our rating: Thick

It was definitely thicker but I would call it “smooth and creamy” to best describe the texture.

I mixed it the way I always do (the bag recommends mixing it with 6-8fl oz of water or milk, but I usually do anywhere between 12-16oz. There were no issues, and I found it mixed well with that amount of water without tasting “watered down.”

I found my sweet spot closer to 12 oz of whole milk, almond milk, or water per 1 scoop serving. 

Satiety

Our rating: 3/5

I digested this quickly (like most whey proteins should) and didn’t get overly stuffed. 

It is important also to point out that whey protein is not supposed to keep you full, but rather, it’s supported to be absorbed quickly. 

For this reason, I will give it a 3 out of 5 rating because I feel it is exactly where it should be (5 out of 5 means it keeps you full, and 1 out of 5 means it doesn’t give you any satiety at all).

Who Is Kirkland Whey Protein For? 

Kirkland Whey Protein is a suitable option for:

• Anyone on a budget looking for an affordable protein powder with a decent amount of protein per serving.

• Someone who struggles with protein powders that are bland or watery, and don’t mix well.

• People with food allergies or sensitivities: Kirkland is soy-free and gluten-free.

Who Shouldn’t Take Kirkland Whey Protein?

Kirkland Whey Protein is not for: 

• Anyone looking for a lot of flavor variety

• Someone whose priority is a third-party-tested product 

• Someone who is an elite athlete

• Somebody looking for a protein powder to keep them full for several hours 

• Someone who wants a protein powder with minimal to no artificial sweeteners or thickeners.

Kirkland Whey Protein Customer Reviews

Kirkland Whey Protein received a 3.9 out of 5 stars on its website based on 41 reviews. This is not a huge number of reviews; however, this is expected as it just launched.

A common thread across many of the reviews was the good taste and high value. It received many 5-star reviews (23 of the 41 reviews), all saying they were blown away by the taste, mixability, and value.

5-star reviewer said: 

“I have used several different brands of protein powder over the years, primarily Gold Standard 100% Whey, and I have to say this is a great product. Despite other reviews, I enjoy the taste and it mixes very well in a blender bottle. At this price point, you honestly can’t beat this protein powder. Hoping Kirkland comes out with vanilla in the future.”

However, some lower-star reviews mentioned issues with mixing (which I didn’t find at all), noting it can be clumpy or frothy. A few reviewers also wished for more flavor options beyond chocolate. Despite the criticisms, many still found the product satisfactory for its price point.

Kirkland Whey Protein Promotions & Discounts

Kirkland Whey Protein is offered exclusively at Costco stores and online. Costco will run promotions every month. However, it is unknown when and if this product will be discounted. You can look online for promotions or sign up for their monthly newsletter that shows you all the promotions available each month.

Where To Buy Kirkland Whey Protein? 

The only place to purchase Kirkland Whey Protein is through the Costco website or at a Costco Warehouse store. First, go on the website and ensure the Costco store near you has them in stock before you go. If they don’t, Costco offers shipping to all US states.

Frequently Asked Questions

Where Is Kirkland Whey Protein Made? 

According to the label, the product was distributed from Washington, United States. It is unclear if this is where it was manufactured.

What Is Costco’s Shipping Policy? 

Costco offers standard shipping rates through UPS and express shipping options. You can determine the cost of your shipping at checkout. That said, my shipping was included in my final price, so depending on where you are in the country it may be included!

What Is Costco’s Return Policy? 

Costco has an amazing return policy. If you are not completely happy with the product, you can return it to any of the 800 Costco Warehouses worldwide. I did not see a time frame on the return policy, but I would have to assume the product should not have been used (meaning, don’t return an empty bag and say you didn’t like it).

Is Kirkland Whey Protein Good For Weight Loss? 

Kirkland Whey Protein states on its label that the product is not intended for weight loss. That said, consuming low-calorie, protein-rich foods is a great way to preserve lean muscle mass when in a calorie deficit. 

Is Kirkland Whey Protein Gluten Free? 

Kirkland Whey Protein is gluten-free; however, it has not been tested by third parties.

What Are The Best Ways To Mix Kirkland Whey Protein? 

Kirkland Whey Protein mixes well in water, milk, and oatmeal.  I consumed it daily using one (if not more than one) of the methods above. I would either mix the powder in my shaker or a blender. When mixed with oatmeal in the morning, I would mix it with water and oat and microwave it (and add some peanut butter), and it was DELICIOUS.

What Flavors Are Available For Kirkland Whey Protein? 

Currently, Kirkland only offers one flavor of their whey protein powder: creamy chocolate.

Can you use Kirkland Whey Protein as A Meal Replacement? 

Kirkland Whey Protein is not a good meal replacement on its own since it is a lower-calorie and faster-digesting protein. However, you can use it to boost the protein content of other foods, such as oatmeal and yogurt, or pair it with lower-protein meals.

When Is The Best Time To Take Kirkland Whey Protein?

Kirkland is suitable for any time of day, as it includes both whey concentrate and isolate (isolate is fast digesting). You can enjoy this pre / post workout, throughout the day, or any time where extra protein might be desired. 

How To Contact Costco

The Kirkland Whey Protein product has the contact information of the bag, as well as on the website. 

Phone: 1-800-433-1213

Link: https://customerservice.costco.com/ 

Connect on social media with Costco on Instagram (not sure how active their DMs are, however it seems they do a few posts a week). I would default to contacting them via phone or the website.

References

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Whitehead A, Beck EJ, Tosh S, Wolever TM. Cholesterol-lowering effects of oat β-glucan: a meta-analysis of randomized controlled trials. Am J Clin Nutr. 2014 Dec;100(6):1413-21. doi: 10.3945/ajcn.114.086108. Epub 2014 Oct 15. PMID: 25411276; PMCID: PMC5394769.