Best Protein Bars at Costco in 2026: 10 Bulk Boxes Ranked

The best protein bars at Costco right now are Quest for overall nutrition, Kirkland Signature for value, and IQBAR if you want a plant-based bar with no sugar alcohols. We checked the bars currently sold in US warehouses and on Costco.com, pulled each one's current Nutrition Facts panel, and ranked all 10 by protein quality, ingredients, and cost per bar.

One thing to know before you go: Costco's bar lineup rotates. Some boxes are permanent, some show up as seasonal or roadshow items, and prices vary by region. The prices below are what we found in October 2026. Online and same-day delivery prices usually run higher than in the warehouse.

Costco Protein Bars at a Glance

Bar	Box	Protein	Calories	Sugar	Price per Bar
1. Quest	14 or 16 ct	21g	190	1g	About $1.69-1.79
2. Kirkland Signature	20 ct	21g	190	2g	About $0.92-1.30
3. IQBAR	18 ct	12g	160-180	1g	About $1.03
4. David	12 ct	28g	150	0g	About $2.08
5. RXBAR	14 ct	12g	210	13-14g	About $1.50
6. ONE	16 ct	20g	220	1g	About $1.06-1.43
7. Pure Protein	25 ct	21g	180	3g	About $1.18
8. FITCRUNCH (16g size)	18 ct	16g	190	3g	About $1.11-1.28
9. Built Puff	14 ct	15-17g	140	Varies	About $1.42
10. CLIF Builders	18 ct	20g	About 290	17-18g	About $1.25-1.38

Nutrition shown for the most common flavor in each Costco box. Prices vary by warehouse and change often.

1. Quest Protein Bars: Best Overall

Quest is the best all-round bar in the warehouse. Its 21g of protein comes entirely from milk protein isolate and whey protein isolate, with no collagen padding, and Chocolate Chip Cookie Dough adds 12g of fiber with only 1g of sugar. Costco carries a 14-count variety pack (about $24.99) and, in many warehouses, a 16-count Chocolate Chip Cookie Dough and Cookies & Cream box (about $26.99).

The downside is the sweetener system: erythritol, stevia, and sucralose, plus soluble corn fiber or polydextrose. Read our full Quest review.

Chocolate Chip Cookie Dough (60g): 190 calories | 21g protein | 22g carbs | 12g fiber | 1g sugar

✅ 21g milk and whey protein, no collagen
✅ High fiber, low sugar
❌ Sucralose and erythritol
❌ Pricier than Kirkland

2. Kirkland Signature Protein Bars: Best Value

Kirkland bars are Costco's answer to Quest, and the macros are close: 21g of protein from milk and whey protein isolates, 190 calories, and 2g of sugar. At roughly $18.49 to $26 for 20 bars depending on the warehouse, they are the cheapest high-protein bar in the store.

They are not identical to Quest, though. Current labels show 10g of fiber (older boxes listed more), and the ingredient list includes soluble corn fiber, isomalto-oligosaccharides (IMO), erythritol, and stevia. IMO is partly digested like a starch, so the bar may affect blood sugar more than its fiber number implies. The Chocolate Chip Cookie Dough flavor also contains cashew butter, so it is not safe for tree nut allergies. See our Kirkland protein bar review.

Chocolate Chip Cookie Dough (60g): 190 calories | 21g protein | 22-23g carbs | 10g fiber | 2g sugar | 7g fat

✅ Lowest price per gram of protein at Costco
✅ 21g of milk and whey protein
❌ Contains IMO
❌ Contains cashews

3. IQBAR: Best Plant-Based Bar

IQBAR's 18-count variety box (Chocolate Sea Salt, Peanut Butter Chip, and Almond Butter Chip) is the best pick at Costco if you want plant protein and no sugar alcohols. Each bar has 12g of protein from pea protein and nuts, 9g of fiber, and about 1g of sugar, sweetened with stevia. It is also the lowest carb bar on this list at roughly 3g of net carbs.

At 12g, protein is lower than the dairy bars. If you want a post-workout bar, Quest or Kirkland will get you closer to 20g.

Peanut Butter Chip (45g): 160-180 calories | 12g protein | 12g carbs | 9g fiber | 1g sugar

✅ No sugar alcohols
✅ Vegan, low net carbs
❌ Only 12g protein
❌ Contains nuts

4. David Protein Bars: Most Protein Per Calorie

Costco added a 12-count David variety pack in 2026 at about $24.99, or roughly $2.08 per bar, which is well below David's own retail price. Each bar has 28g of protein and 150 calories, the best protein-to-calorie ratio you can buy.

The fine print: the protein blend includes collagen alongside milk protein isolate, whey, and egg white, and the bar uses maltitol, allulose, soluble corn fiber, sucralose, acesulfame potassium, and a modified fat called EPG. Read our David protein bar review for the details.

David Gold: 150 calories | 28g protein | 12g carbs | 0g sugar | 2.5g fat

✅ 28g protein in 150 calories
✅ Good Costco discount
❌ Collagen in the protein blend
❌ Long list of sweeteners and modified ingredients

5. RXBAR: Simplest Ingredient List

RXBAR is the closest thing to a whole-food bar at Costco. The Chocolate Sea Salt bar is made from egg whites, dates, cashews, almonds, chocolate, cocoa, natural flavors, and sea salt. There are no sugar alcohols, no protein isolates, and no added sugar.

The catch is that all the sweetness comes from dates, so a bar has 13 to 14g of sugar, and protein is only 12g. RXBAR also contains nuts and eggs. See our RXBAR review.

Chocolate Sea Salt (52g): 210 calories | 12g protein | 23g carbs | 5g fiber | 13-14g sugar (0g added)

✅ Short, recognizable ingredient list
✅ No added sugar or sugar alcohols
❌ 13 to 14g of sugar from dates
❌ Only 12g protein

6. ONE Protein Bars: Best Dessert Flavors

ONE's 16-count variety pack brings flavors like Birthday Cake to Costco, and Costco also sells a Reese's ONE bar (18g protein, 3g sugar). Birthday Cake has 20g of protein and 1g of sugar for 220 calories. Sweetness comes from maltitol syrup and sucralose, and the bar also uses processed fibers like IMO and polydextrose. See our ONE bar review.

Birthday Cake (60g): 220 calories | 20g protein | 22g carbs | 9g fiber | 1g sugar

7. Pure Protein: Cheapest 20g+ Bar From a National Brand

Pure Protein is one of the most affordable bars at Costco, often around $1.18 per bar in the larger variety pack. Chocolate Deluxe has 21g of protein, 180 calories, and 3g of sugar. But the protein includes hydrolyzed collagen, the bar uses maltitol and maltitol syrup, and fiber is only 2g. See our Pure Protein review.

Chocolate Deluxe (50g): 180 calories | 21g protein | 17g carbs | 2g fiber | 3g sugar | 4g sugar alcohol

8. FITCRUNCH: Best Taste and Texture

The 18-count box at Costco is the smaller 16g protein FITCRUNCH bar, not the 30g full-size version. It is a six-layer baked bar that eats like a candy bar, with 190 calories and 3g of sugar. If taste is your top priority, this is the one. See our FITCRUNCH review.

Chocolate Peanut Butter (46g): 190 calories | 16g protein | 3g sugar | 4g saturated fat

9. Built Puff: Lightest Option

Built Puff bars are airy, marshmallow-style bars at only about 140 calories each. Costco's 14-count boxes rotate flavors (recent packs paired Strawberries 'N Cream with Cookies 'N Cream). Protein runs 15 to 17g, but the protein blend pairs whey with collagen (some flavors list collagen first), and gelatin helps create the texture, so it is not the best choice for muscle building. See our Built Bar review.

10. CLIF Builders: Skip Unless You Need the Calories

CLIF Builders has 20g of soy protein, but also about 290 calories and 17 to 18g of sugar, which puts it closer to a candy bar than a protein bar on sugar. It is a reasonable pick for a long hike or a hard training day, not for an everyday snack. Our CLIF Bar review covers the full lineup, including the newer reduced-sugar version.

Chocolate Peanut Butter (68g): about 290 calories | 20g protein | 30g carbs | 2g fiber | 17-18g sugar

How to Shop Costco's Protein Bar Aisle

• Compare protein source, not just grams. Quest and Kirkland use milk and whey isolates. David, Pure Protein, and Built Puff count collagen toward their totals, and collagen does less for muscle.
• Know which sugar alcohol you are getting. Erythritol (Quest, Kirkland) is better tolerated than maltitol (Pure Protein, ONE, David). If bars upset your stomach, maltitol is the usual suspect. Our guide to sugar alcohols in protein bars explains the differences.
• Check the box size. FITCRUNCH and some ONE boxes at Costco are smaller bars than the versions sold elsewhere.
• Try before you commit. An 18 to 25-count box is a big bet on a flavor you have never tried. Buy a single bar at a grocery store first, or start with a variety pack.
• Watch the end caps. Costco runs frequent instant savings on bars. Quest and CLIF Builders boxes in particular drop sharply on clearance.

Want a Cleaner Bar Than Costco Carries?

Every high-protein bar at Costco gets there with protein isolates, processed fibers, or sugar alcohols. If you want a bar built from whole-food ingredients, the LyfeFuel Essentials Bar uses pea and almond protein with no sugar alcohols, no artificial sweeteners, and no collagen. It has 14g of fiber, 1g of added sugar, and 25% of the Daily Value for 21 vitamins and minerals from a whole-food blend. At 11g of protein it is an everyday snack, not a post-workout bar.

Shop the LyfeFuel Essentials Bar

Shopping elsewhere? See the best protein bars at Walmart, Trader Joe's, and Whole Foods.

Which Costco Protein Bar Should You Buy?

If You Want	Buy
Best nutrition overall	Quest
Lowest price for 20g+ protein	Kirkland Signature
Plant-based, no sugar alcohols	IQBAR
Most protein per calorie	David
Simplest ingredients	RXBAR
Best taste	FITCRUNCH

Frequently Asked Questions

What is the best protein bar at Costco?

Quest is the best overall protein bar at Costco: 21g of milk and whey protein, 12g of fiber, and 1g of sugar, with no collagen. Kirkland Signature is the best value, and IQBAR is the best plant-based pick.

Are Kirkland protein bars the same as Quest bars?

No. They have similar macros (21g protein, about 190 calories), but Kirkland bars contain isomalto-oligosaccharides (IMO) and, in the Chocolate Chip Cookie Dough flavor, cashew butter. Current Kirkland labels also show less fiber than Quest (10g vs 12g).

How much are protein bars at Costco?

In October 2026 most Costco protein bars worked out to about $1 to $2 per bar. Kirkland Signature was cheapest at roughly $0.92 to $1.30 per bar, and David was the most expensive at about $2.08. Prices vary by warehouse.

Does Costco sell David protein bars?

Yes. Costco added a 12-count David variety pack in 2026, priced around $24.99 in the warehouse. Availability varies by location.

Are Costco protein bars healthy?

Some are better than others. Quest, Kirkland, and IQBAR are low in sugar with solid protein. RXBAR has the simplest ingredients but more sugar. CLIF Builders has 17 to 18g of sugar, so it is better treated as an energy bar.

What protein bars does Costco sell?

Current US Costco protein bars include Kirkland Signature, Quest, IQBAR, David, RXBAR, ONE, Pure Protein, FITCRUNCH, Built Puff, and CLIF Builders. The selection rotates, so not every warehouse carries every bar.

Sources: Costco.com and Costco same-day listings, warehouse price trackers, brand product pages, and retailer Nutrition Facts panels, checked October 2026. Prices are approximate and vary by location. Formulas change; always read the package.