Is Costco Dog Food Made by Diamond Naturals? The Ultimate Guide

For pet owners who prioritize their dogs’ health and nutrition, choosing the right dog food brand is a critical decision. One brand that often comes up in discussions about quality canine nutrition is Diamond Naturals. At the same time, Costco has earned a reputation for offering high-quality bulk goods—including premium pet food—at affordable prices. This has led many to wonder: Is Costco dog food made by Diamond Naturals? While the answer might seem straightforward, the story behind the brands, manufacturers, and product lines is more nuanced. In this comprehensive guide, we’ll explore the connection between Costco’s dog food offerings and Diamond Pet Foods, the company behind Diamond Naturals. You’ll learn about manufacturing processes, ingredient quality, store-brand formulations, and how to make an informed choice for your furry family member.

The Origins: Who Makes Diamond Naturals?

Diamond Naturals is a premium dog food brand produced by Diamond Pet Foods, a company founded in 1928 and headquartered in Meta, Missouri. Known for its commitment to high-quality ingredients and science-based nutrition, Diamond Pet Foods operates several manufacturing facilities across the United States—including locations in California, Arkansas, and South Carolina. The company has consistently marketed its products as using real meat, fruits, vegetables, and superfoods to support canine health, including strong immunity, healthy skin and coat, and optimal digestion.

Diamond Naturals itself launched as a response to growing consumer demand for natural and minimally processed pet foods. The brand features formulations that include:

• Real meat as the first ingredient
• Omega fatty acids for skin and coat health
• Probiotics and a proprietary blend of superfoods
• Free from artificial colors, flavors, and preservatives

But while Diamond Naturals is available in many stores, including online retailers and pet specialty chains, it’s notably absent from Costco’s shelves. This absence raises the larger question of whether Diamond is involved behind the scenes with Costco’s own private-label dog food.

Costco’s Kirkland Signature Dog Food: What Is It?

Costco’s private-label pet food—sold under the Kirkland Signature brand—is one of the most popular premium dog foods available in bulk. It’s designed to offer an excellent balance of nutrition, quality, and value, making it a favorite among dog owners looking to stretch their dollar without compromising on health essentials.

Kirkland Signature offers several dog food formulas, including:

• Kirkland Signature Puppy Formula (grain-inclusive)
• Kirkland Signature Adult Formula (grain-inclusive)
• Kirkland Signature Adult Grain-Free Formula
• Kirkland Signature Small Breed Formula

These formulas are typically sold in large 30- to 40-pound bags, which help reduce packaging waste and lower the cost per pound compared to most national brands.

Manufacturer Behind Kirkland Signature Dog Food

Despite speculation, Costco does not manufacture its own dog food. Instead, it contracts third-party manufacturers to produce Kirkland Signature products under strict quality control guidelines. When it comes to dog food, Costco has partnered with Diamond Pet Foods in the past—but with important caveats.

Yes, Diamond Pet Foods did produce Kirkland Signature dog food during the mid-2010s. However, this partnership has evolved over time. In fact, the formulation and manufacturing of Kirkland dog food have changed multiple times, depending on Costco’s sourcing strategies and manufacturer agreements.

Historically, many analysts noted significant similarities between the ingredient profiles of Kirkland Signature formulas and Diamond Naturals. For example:

These overlaps led many pet nutrition bloggers and buyers to believe that Diamond Naturals and Kirkland dog food were practically cousins under the same roof. However, ingredient lists alone do not confirm manufacturing relationships, and formulations can be replicated independently.

Is Diamond Pet Foods Still Making Costco Dog Food?

The current answer, as of mid-2024, is no—at least not definitively. Industry sources and label investigations suggest that Costco has transitioned the production of its Kirkland Signature dog food to another major pet food manufacturer. Several lines are now reportedly produced by Wells Enterprise, Inc. (also known as Wells Pet Food Company), a Midwest-based co-manufacturer that produces food for several private-label brands.

Why did Costco switch manufacturers? While Costco has not publicly disclosed specific reasons, common industry drivers include:

• Contract expirations
• Changes in ingredient sourcing
• Strategic cost reductions
• Scaling up production capacity
• Safety and recall history

It’s worth noting that Diamond Pet Foods has had past recalls due to contamination issues (including salmonella), which may have influenced Costco’s decision to diversify its manufacturing base.

While Costco maintains high standards for all Kirkland products, the change in manufacturer means that today’s Kirkland dog food is no longer made by the same facility that produced it during its Diamond-era.

Comparing Kirkland and Diamond Naturals: Nutritional Differences

Even if they’re no longer made by the same company, it’s useful to compare the two brands side-by-side. Let’s examine their similarities and differences in key nutritional areas.

Protein Sources and Ingredients

Both Kirkland Signature and Diamond Naturals typically use chicken (or chicken meal) as a primary protein source. However, differences emerge in ingredient quality and transparency.

Kirkland Signature Adult Dog Food currently includes:

• Chicken meal
• Brown rice
• Barley
• Oats
• Chicken fat (preserved with mixed tocopherols)
• Flaxseed
• Dried beet pulp
• Natural flavor
• Vitamins and minerals

Diamond Naturals Adult Large & Medium Breed formula includes:

• Chicken
• Chicken meal
• Peas, sweet potatoes, and potatoes
• Pea protein
• Canola oil
• Dried fruits and vegetables (kale, pumpkin, carrots)
• Probiotic cultures
• Superfood blend (blueberries, cranberries, etc.)

The shift from whole meat to “meal” in Kirkland’s formula can indicate concentration and longer shelf life, but some pet owners prefer formulas with fresh or whole meat as the first ingredient.

AAFCO Nutritional Adequacy

Both brands are formulated to meet the nutritional levels established by the AAFCO Dog Food Nutrient Profiles for all life stages or specific stages (e.g., adult maintenance or growth). This means both have undergone feeding trials or nutrient analysis to prove they provide complete and balanced nutrition.

However, Diamond Naturals explicitly states on its packaging that many of its formulas are “recommended for all life stages,” whereas Kirkland’s labeling varies slightly by formula, often specifying suitability for adult or puppy life stages.

Pricing and Value: Costco vs. Diamond Naturals

One of the biggest advantages of Kirkland Signature dog food is its price-to-quality ratio. A 30-pound bag typically costs between $40 and $55, depending on membership and location. That’s roughly $1.33 to $1.83 per pound.

In contrast, Diamond Naturals retails for about $3.50 to $4.00 per pound, depending on retailer and region. This makes Diamond over twice as expensive per unit weight compared to Kirkland.

For a medium-sized dog consuming 2–3 cups per day, the annual savings from choosing Kirkland could exceed $300. For budget-conscious families, that’s a compelling advantage.

Quality Control and Recall History

When evaluating pet food brands, safety is as important as nutrition. Let’s review the recall history of both Diamond Pet Foods and Kirkland Signature.

Diamond Pet Foods: Recall Incidents

Over the past two decades, Diamond Pet Foods has had multiple recalls, primarily due to potential salmonella contamination. These recalls were typically precautionary, involving dry kibble where testing revealed the presence of the bacteria. For example:

• 2012: Recall of several Diamond Naturals formulas due to possible salmonella.
• 2013: Another salmonella-related recall affecting grain-free formulas.
• 2014: Expanded recall of dry dog and cat foods.

It’s important to note that no human or pet illnesses were directly reported in many of these cases. The company implemented enhanced safety protocols afterward, including improved quality assurance, sanitation standards, and testing procedures.

Kirkland Signature: A Clean Safety Record

Kirkland Signature dog food has maintained a strong safety record over the years. While some pet owners have reported concerns over ingredient changes or palatability shifts (especially after the manufacturer change), there have been no major recalls tied specifically to the Kirkland adult or puppy formulas produced for Costco.

This absence of recalls contributes to consumer trust in the brand, particularly when compared to other premium-grade foods with similar formulas that have experienced contamination problems.

Expert Opinions: What Do Veterinarians Say?

Veterinarians and pet nutritionists often evaluate dog foods based on protein content, digestibility, and adherence to AAFCO standards. While opinions vary, many professionals hold Kirkland Signature in high regard.

Dr. Jennifer Coates, a veterinary advisor for PetMD, has described Kirkland’s formulas as “nutritionally sound and appropriate for most healthy adult dogs,” especially when considering their price point. She noted that the use of chicken meal as a primary protein source is effective and common in high-quality pet foods.

Similarly, veterinary nutritionists often praise Diamond Naturals for its inclusion of superfoods, probiotics, and whole-food ingredients. However, they caution that “natural” does not always mean “better,” especially if a dog has specific health conditions.

When asked to compare the two, many experts agree:

• Both brands provide complete nutrition for healthy dogs.
• Kirkland offers greater value and long-term affordability.
• Diamond Naturals may appeal to owners seeking variety in protein sources and more plant-based nutritional additives.

Limitations to Consider

Despite their advantages, neither food is ideal for every dog:

• Kirkland Signature is not available in wet or canned formats, limiting meal variety.
• Some dogs may be sensitive to grain-inclusive formulas, although grain-free versions exist.
• Diamond Naturals, while more diverse, can be cost-prohibitive for large-breed dogs.
• Neither brand currently offers prescription diets or veterinarian-restricted formulas.

For dogs with health issues such as food allergies, pancreatitis, or renal disease, a vet-recommended therapeutic food may be necessary—regardless of the quality of over-the-counter options.

Common Misconceptions About Private-Label Pet Foods

Part of the confusion about Kirkland Signature and Diamond Naturals stems from widespread misconceptions about store-brand pet foods. Let’s clarify a few:

Misconception 1: “Private Label = Lower Quality”

This myth persists, but it’s outdated. Kirkland Signature, like many premium private-label brands, is formulated to match or exceed national brands. Costco’s buyer specifications are famously stringent, requiring manufacturers to meet high standards for ingredient sourcing, cleanliness, and nutritional balance.

Misconception 2: “If a Food Was Made by a Known Brand, It’s the Same”

Just because Diamond Pet Foods once produced Kirkland dog food does not mean the formulas were identical. Costco owns the recipe and brand, so it can demand custom formulations even when working with a third-party manufacturer. The original Kirkland recipe was never publicly labeled as “made by Diamond Naturals”—it was simply made by the same parent company, under different branding.

Misconception 3: “Changing Manufacturers Ruins the Food”

Manufacturer changes can affect texture, kibble size, or shelf life, but not necessarily nutritional quality. Costco likely tested new formulations extensively before rolling out the switch. While some pet owners reported temporary palatability issues after the change, most dogs adjusted well.

How to Choose the Right Food for Your Dog

With so many options—and so much conflicting information—how can you make the best choice?

Key Factors to Evaluate

Life Stage and Size

Choose a formula appropriate for your dog’s life stage: puppy, adult, or senior. Small, medium, and large breeds have differing nutritional needs. For example, large-breed puppies need controlled calcium levels to avoid joint problems, while small breeds may require higher energy density.

Activity Level

Active dogs, working dogs, or those in cold climates may need higher fat and calorie content. Sedentary or indoor dogs may benefit from lower-calorie formulas to prevent obesity.

Allergies and Sensitivities

If your dog has allergies, look for limited-ingredient diets or formulas free of common allergens like chicken, beef, or grains. Some dogs do well on alternative proteins such as lamb, salmon, or duck.

Budget and Long-Term Use

As discussed, Kirkland offers significant savings. For families feeding large or multiple dogs, this can mean hundreds of dollars saved annually. However, if your dog requires a hypoallergenic or novel protein formula, the higher cost of brands like Diamond Naturals might be justified.

Final Thoughts: Is Costco Dog Food Made by Diamond Naturals?

To summarize the original question: Is Costco dog food made by Diamond Naturals?

The answer is no, not currently. While Diamond Pet Foods did manufacture Kirkland Signature dog food in the past, production has since shifted to another facility. Additionally, although the ingredient profiles of the two brands were once similar, they have diverged over time.

Costco’s Kirkland Signature remains a high-quality, veterinarian-approved option, especially for owners seeking cost-effective yet nutritious dog food. Diamond Naturals continues to be a strong choice for those who prioritize natural ingredients, superfoods, and brand consistency.

Ultimately, the best dog food for your pet depends on individual needs—not brand origin or past manufacturing ties. By understanding the facts about who makes what—and why—you can make informed choices that support your dog’s health, happiness, and longevity.

If you’re considering a switch to Kirkland or Diamond Naturals, consult your veterinarian first. Transition foods gradually over 7–10 days, and monitor your dog for energy levels, coat quality, and stool consistency. Whether you choose bulk-value from Costco or premium ingredients from Diamond Naturals, your dog’s well-being comes first.

Is Costco dog food made by Diamond Naturals?

No, Costco dog food is not made by Diamond Naturals. While Diamond Naturals is a well-known brand in the pet food industry, the dog food sold under brands like Kirkland Signature at Costco is typically produced by other major pet food manufacturers. These products are often developed specifically for Costco through partnerships with co-manufacturers that meet the company’s stringent quality standards.

Kirkland Signature dog food, for example, has previously been produced by Diamond Pet Foods, which may have led to confusion between Diamond Naturals and Diamond Pet Foods. It’s important to note that Diamond Pet Foods is the manufacturer, while Diamond Naturals is a premium line of products offered by the same company. However, recent formulations and sourcing changes mean that production may now occur through different facilities or partners. Always check packaging details or contact Costco directly for the most accurate information.

What brands of dog food does Costco sell?

Costco offers a wide selection of both in-house and national dog food brands. The most popular in-house brand is Kirkland Signature, which includes dry and wet food formulas for all life stages and specific dietary needs, such as grain-free or specialty protein options. These formulations are designed to offer high nutritional value at a competitive price, aligning with Costco’s bulk retail model.

In addition to Kirkland Signature, Costco carries well-known national brands such as Science Diet, Royal Canin, Nutro, Blue Buffalo, and Wellness. The availability of these brands may vary by location and over time, depending on supply agreements and customer demand. Costco’s selection is carefully curated to balance quality, affordability, and variety, ensuring pet owners can find suitable options for their dogs, whether they require prescription diets or high-protein, grain-free formulas.

Who actually manufactures Kirkland Signature dog food?

Kirkland Signature dog food has been manufactured by several different producers over the years, based on supply contracts and regional availability. One of the most recognized manufacturers formerly involved was Diamond Pet Foods, a major U.S.-based pet food company known for producing multiple private-label brands. However, the manufacturing partner may differ now depending on the specific Kirkland formula and where it’s distributed.

Manufacturing details are not always listed directly on the packaging, but batch codes and ingredient sourcing can provide clues about where the product was made. Costco maintains strict quality control and often audits its suppliers, ensuring that safety and nutritional standards are upheld regardless of the manufacturer. For definitive information, contacting Costco’s customer service or visiting the Kirkland Signature official website can clarify current production partners.

Is Kirkland Signature dog food comparable to Diamond Naturals in quality?

Kirkland Signature dog food is competitively formulated to offer similar nutritional profiles to premium brands like Diamond Naturals, especially given their past connections through Diamond Pet Foods. Kirkland’s recipes typically feature high-quality ingredients such as real meat as the first ingredient, balanced levels of protein and fat, and added vitamins and minerals. Many customers find the quality-to-price ratio excellent, particularly for a private-label brand sold in bulk.

While Diamond Naturals positions itself as a premium, naturally sourced brand often found in pet specialty stores, Kirkland Signature provides a cost-effective alternative without significant compromise on quality. Both brands avoid artificial preservatives, colors, and flavors, and emphasize digestibility and palatability. However, pet owners with specific needs—such as sensitive stomachs or breed-specific requirements—may still prefer Diamond Naturals’ targeted formulas. It’s recommended to evaluate individual dog needs before deciding between the two.

Why is there confusion between Diamond Naturals and Costco dog food?

The confusion stems from the historical relationship between Diamond Pet Foods and Kirkland Signature. Diamond Pet Foods, the parent company behind the Diamond Naturals brand, once manufactured dog food for Costco under the Kirkland Signature label. Because both products were connected through the same manufacturer, many consumers assumed Kirkland’s formulas were simply rebranded Diamond Naturals, leading to lasting misconceptions.

Additionally, packaging aesthetics, ingredient profiles, and similar marketing language emphasizing natural components contribute to the confusion. However, being manufactured by the same company doesn’t make the formulas identical. Kirkland’s recipes are developed independently to meet Costco’s cost and volume requirements, while Diamond Naturals targets a different market segment with higher price points and specific branding. Clearer labeling and public education have helped, but misunderstandings persist.

How can I check where my Kirkland dog food was made?

To determine where your Kirkland Signature dog food was manufactured, examine the packaging for production details such as the manufacturing lot number, facility code, or “Made in USA” labeling. Some bags include a statement identifying the plant location or the company responsible for production. While the primary brand is Kirkland, co-manufacturers may be disclosed in fine print or through batch-specific traceability systems.

You can also contact Costco’s member services with the lot number and product details to request information about the manufacturing source. Their customer support team can provide clarity on current production partners and facility standards. Additionally, third-party pet food analysis websites sometimes track and report on manufacturing origins based on publicly available data and consumer reports.

Is Diamond Pet Foods the same as Diamond Naturals?

Diamond Pet Foods is the manufacturing company, while Diamond Naturals is one of the premium product lines it produces. Diamond Pet Foods operates multiple brands and also produces food for private-label clients, including retail chains. Diamond Naturals, on the other hand, is marketed as a high-end, natural pet food line emphasizing real ingredients, superfoods, and species-appropriate nutrition.

The distinction is important because not all products made by Diamond Pet Foods carry the same quality claims as Diamond Naturals. For example, some of their other lines, like Diamond Basics or 4Health, may have different formulations or target different segments of the market. Being aware of this helps consumers understand that while a product might be made by Diamond Pet Foods, it doesn’t automatically mean it’s equivalent to the Diamond Naturals brand.