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  3. Kirkland Signature
Kirkland Signature logo

Kirkland Signature Supplements

Kirkland Signature is Costco Wholesale's premium private-label brand, offering a wide range of vitamins and nutritional supplements manufactured under rigorous quality controls. Many products carry the USP Verified mark from the United States Pharmacopeia, an independent organization that sets strict quality and purity standards. All supplements are designed to meet or exceed the quality of national brands at an exceptional value for Costco members.

Founded

1995

Country

US

Products

26

Avg. Score

80.8/100

Visit Kirkland Signature Website →
TL;DR

Kirkland Signature at a glance — here's what our analysis found.

  • •26 products analyzed
  • •Average quality score: 80.8/100
  • •26 verified products
  • •Top ingredient: Vitamin D (in 9 products)
26 products analyzed
by Kirkland Signature for quality and ingredient transparency
Source: StackAura Database
80.8/100
average quality score across 26 verified products
Source: StackAura Database

All Kirkland Signature Products

Chewable Vitamin C 500 mg

Chewable Vitamin C 500 mg

Score:93/100
Verified

$17.99

Quick Dissolve B-12 5000 mcg

Quick Dissolve B-12 5000 mcg

Score:91/100
Verified

$18.99

Glucosamine with MSM

Glucosamine with MSM

Score:89/100
Verified

$15.99

Calcium 600 mg with Vitamin D3

Calcium 600 mg with Vitamin D3

Score:87/100
Verified

$5.49

CoQ10 300 mg

CoQ10 300 mg

Score:86/100
Verified

$15.99

Wild Alaskan Fish Oil 1400 mg

Wild Alaskan Fish Oil 1400 mg

Score:85/100
Verified

$26.99

Glucosamine & Chondroitin

Glucosamine & Chondroitin

Score:85/100
Verified

$17.49

Vitamin E 180 mg (400 IU)

Vitamin E 180 mg (400 IU)

Score:85/100
Verified

$9.49

Daily Multi Vitamins & Minerals

Daily Multi Vitamins & Minerals

Score:85/100
Verified

$12.99

Magnesium Citrate 250 mg

Magnesium Citrate 250 mg

Score:84/100
Verified

$18.99

Turmeric 1000 mg

Turmeric 1000 mg

Score:84/100
Verified

$32.49

USDA Organic Multivitamin

USDA Organic Multivitamin

Score:83/100
Verified

$17.49

Super B-Complex with Electrolytes

Super B-Complex with Electrolytes

Score:82/100
Verified

$15.99

Adult 50+ Mature Multi Vitamins & Minerals

Adult 50+ Mature Multi Vitamins & Minerals

Score:82/100
Verified

$12.99

Adult Multivitamin Gummies

Adult Multivitamin Gummies

Score:81/100
Verified

$13.99

Fish Oil 1000 mg

Fish Oil 1000 mg

Score:80/100
Verified

$15.99

Extra Strength Vitamin D3 2000 IU

Extra Strength Vitamin D3 2000 IU

Score:80/100
Verified

$7.99

Calcium 500 mg with D3 & Zinc Adult Gummies

Calcium 500 mg with D3 & Zinc Adult Gummies

Score:79/100
Verified

$19.99

Vitamin C 1000 mg with Rose Hips

Vitamin C 1000 mg with Rose Hips

Score:79/100
Verified

$15.99

Vitamin C 250 mg Adult Gummies

Vitamin C 250 mg Adult Gummies

Score:79/100
Verified

$16.99

Children's Complete Multivitamin Gummies

Children's Complete Multivitamin Gummies

Score:78/100
Verified

$13.49

Calcium Citrate, Magnesium and Zinc

Calcium Citrate, Magnesium and Zinc

Score:78/100
Verified

$14.99

Krill Oil 500 mg

Krill Oil 500 mg

Score:76/100
Verified

$25.99

Triple Action Joint Health

Triple Action Joint Health

Score:71/100
Verified

$17.99

Daily Probiotic 30 Billion

Daily Probiotic 30 Billion

Score:63/100
Verified

$22.99

OPTIFIBER Prebiotic Fiber Supplement

OPTIFIBER Prebiotic Fiber Supplement

Score:56/100
Verified

$19.99

Quality Analysis

Based on our analysis of 26 products from Kirkland Signature:

  • Average health score: 80.8/100
  • 26 products verified for ingredient accuracy
  • Most commonly used ingredient: Vitamin D
  • Product range spans 10 different supplement categories

Most Common Ingredients

1

Vitamin D

Found in 9 products

2

Vitamin C

Found in 9 products

3

Vitamin B12

Found in 7 products

4

Vitamin E

Found in 6 products

5

Pantothenic Acid

Found in 5 products

6

Vitamin A

Found in 5 products

7

Vitamin B6

Found in 5 products

8

Calcium

Found in 5 products

9

Vitamin B9

Found in 5 products

10

Zinc

Found in 5 products

Frequently Asked Questions

Is Kirkland Signature a good supplement brand?

Kirkland Signature supplements offer outstanding quality for the price. Many carry USP Verified certification, the same rigorous standard used by Nature Made. Independent testing consistently shows Kirkland products meet or exceed label claims. They are manufactured by reputable contract manufacturers to Costco's specifications.

Where to buy Kirkland Signature supplements?

Kirkland Signature supplements are exclusively available at Costco warehouses and Costco.com. You need a Costco membership ($65/year for Gold Star) to purchase. Some products occasionally appear on Amazon through third-party sellers, but buying directly from Costco ensures authenticity and freshness.

Who makes Kirkland Signature supplements?

Costco contracts with reputable supplement manufacturers to produce Kirkland products. While the exact manufacturers are not always publicly disclosed, independent analyses have shown the products meet USP standards. The quality is comparable to national brands like Nature Made at significantly lower prices.

Related Products & Ingredients

Medical Disclaimer: This content is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare provider before starting any supplement regimen.