Costco Overtakes Kroger in U.S. Grocery Spending Share

By Olivia Hart

Costco captured 8.4% of food and beverage spending, ahead of Kroger’s 8.2%, in Numerator’s latest retailer market-share data, taking the No. 2 grocery position in the latest 12 months. The 0.2 percentage-point gap, published Oct. 28, 2026, marks a reversal in the order of the two grocers.

Numerator released its Retailer Market Share update on Wednesday, Oct. 28, 2026. It tracks each retailer’s share of consumer spending across food and beverage and broader consumer packaged goods (CPG) categories over the latest 12 months and updates the measure quarterly.

What do the latest rankings show?

The disclosed percentages are the update’s measurements. Numerator’s broader conclusion—that CPG spending is concentrating around Walmart, Amazon and Costco while Kroger and Albertsons continue to lose ground—is its interpretation of those results.

The top five CPG retailers by spending share:

• Walmart: 20.8%
• Costco: 8.2%
• Amazon + Whole Foods: 8.1%
• Kroger: 6.7%
• Sam’s Club: 3.6%

The top five grocery retailers by spending share:

• Walmart: 20.3%
• Costco: 8.4%
• Kroger: 8.2%
• Albertsons: 4.5%
• Publix: 4.1%

These rankings establish spending allocation, not dollar revenue or unit sales. The figures provided do not include a total market value, so a retailer’s percentage cannot be converted into absolute sales from this update.

The practical result is simple: Costco has passed Kroger in grocery spending, while Walmart remains far ahead in both rankings.

How close is Amazon to Costco?

Amazon + Whole Foods gained 0.7 percentage points of broader CPG share from a year earlier, the largest increase among major retailers. Its 8.1% share put it 0.1 point behind Costco’s 8.2%.

That comparison concerns spending, not units, transactions or marketplace sales volume. The figures do not disclose basket counts, item counts or a split between Amazon and Whole Foods, so they cannot show which channel produced the gain or whether shoppers bought more products. Amazon’s 8.1% spending share should not be read as an 8.1% transaction share.

Separately, Costco gained 0.5 point of broader CPG share, including an 0.8-point increase in the West. Sam’s Club lost 0.2 point nationally.

Costco still leads, but Amazon’s faster growth has compressed the gap to one-tenth of a percentage point.

Can Kroger’s $5 billion price plan reverse the shift?

Kroger has announced plans to invest $5 billion in lower prices to regain competitive ground, putting its price investment directly against Costco’s new 0.2-point grocery lead.

The operating trade-off is clear. Lower prices can improve customer economics—how price, convenience and basket size affect spending—by reducing what shoppers pay and drawing them back. They also pressure gross margin, or sales revenue minus product cost, on each unit sold unless added volume or supplier funding offsets the discount.

Inventory turns, meaning how quickly stock sells and is replenished, could improve if lower prices lift movement and reduce markdown exposure. The figures, however, show no stock or unit-throughput data. The cited data therefore cannot connect Costco’s larger spending share to faster inventory movement.

Channel power, or the ability to secure favorable supplier terms, is also unresolved. The update provides no supplier agreements, discount schedule, funding source or implementation timetable for Kroger’s plan, so it cannot determine who bears the cost of lower prices.

The $5 billion can rebuild traffic, but the figures cannot show whether it protects gross profit or improves inventory turns.

Is Walmart’s lead equally strong across age groups?

Walmart maintained national CPG leadership with 20.8% of spending, up 0.1 point from a year earlier. It also held 20.3% of grocery spending.

Within that aggregate, Walmart’s spending share rose more than 0.6 points among Gen Z and millennial shoppers, while it fell 0.3 points among boomers.

The cohort figures locate the spending shift; they do not disclose cohort size, visit frequency or units purchased. The release therefore supports a generational divide, not a claim that either group bought more groceries in absolute terms.

Walmart’s national lead therefore masks uneven customer momentum rather than a uniform gain.

What can the spending data not settle?

The update answers where spending went, but not whether each retailer created more value. Four operating measures remain absent:

• Gross margin: The figures say nothing about Costco’s 8.4% grocery share or Walmart’s 20.8% CPG share translating into superior gross profit dollars per dollar of sales.
• Inventory turns: No stock levels or unit throughput appear, so faster inventory turns at Costco, Kroger or Amazon cannot be claimed from these results.
• Channel power: Share shifts show where consumers direct their spending, not which retailer has stronger supplier terms, lower freight costs or greater ability to fund discounts.
• Customer economics: A higher spending share can come from more trips, larger baskets or more units. Without basket and trip data, the update cannot distinguish among them.

Accordingly, the moves strengthen Costco’s and Amazon’s position with shoppers, but they do not prove superior profitability, purchasing leverage or basket economics. The evidence establishes share, not the quality of profit behind it.

The next quarterly Numerator update will show whether Costco’s 0.2-point grocery lead and Amazon + Whole Foods’ 0.1-point CPG gap persist as Kroger’s $5 billion price plan takes effect.