Costco has moved ahead of Kroger in its share of U.S. grocery spending, according to Numerator’s latest retail tracking, putting the warehouse club second behind Walmart under that measure.
For the 12 months ending September 30, 2026, Costco captured an estimated 8.4% of food and beverage spending, compared with Kroger’s 8.2%. Walmart remained well ahead of both at 20.3%.
The change highlights the competition for the grocery budget across different retail formats. A warehouse club, a supermarket chain and a mass retailer can compete for the same household spending without offering identical shopping experiences.
It does not establish that Costco is the cheapest choice for every household. Nor does it mean Kroger lost sales dollars simply because its share declined. The finding concerns each retailer’s portion of spending within Numerator’s defined market.
A Narrow Lead, With a Specific Meaning
The Numerator Retail Market Share tracker separates grocery spending from a broader consumer packaged goods category.
For grocery, it measures food and beverage spending across retail channels, including physical stores and e-commerce. Alcohol and cannabis products are excluded.
The leading grocery shares in the latest figures were:
- Walmart: 20.3%.
- Costco: 8.4%.
- Kroger: 8.2%.
- Albertsons: 4.5%.
- Publix: 4.1%.
Costco leads Kroger by 0.2 percentage points. That is a difference in spending share, not a claim that Costco sells 0.2% more individual products or operates more stores.
The ranking also does not compare total corporate revenue. Retailers sell different combinations of food, household merchandise and other products, making those broader totals a separate question.
Costco’s Position Has Improved Over Two Years
The latest result follows a gradual change in the published figures, rather than a single week of shopping.
Costco’s grocery share was 7.7% in the comparable 12-month period ending September 2024 and 7.9% a year later. It reached 8.4% in the latest period.
Kroger’s share moved from 8.7% to 8.4% and then 8.2% across those same reporting periods.
That progression reverses the companies’ positions: Kroger held the larger share two years earlier, while Costco now has the edge.
Numerator’s figures describe where spending went. They do not, by themselves, establish why each shopper chose a store. Price, package size, product selection, and convenience are possible considerations, but the ranking is not a survey assigning a motive to every purchase.
Walmart Still Holds a Substantial Lead
Costco’s move into second place should not obscure the distance between the top two positions.
Walmart’s 20.3% grocery share is more than twice Costco’s 8.4%. Its latest share also exceeds the combined 16.6% held by Costco and Kroger.
The latest grocery spending figures put Costco ahead of Kroger, but still well behind Walmart.
That makes this a change in the order behind the leader, not a challenge to Walmart’s first-place position in the current figures.
For readers, the important distinction is between gaining a position and catching the leader. Costco achieved the former in this dataset; the figures do not establish the latter.
A Grocery Ranking Is Not the Same as a CPG Ranking
The broader consumer packaged goods, or CPG, comparison includes food and beverages alongside selected household, personal care, baby and pet categories.
In that ranking, Walmart held 20.8%, Costco 8.2%, Amazon and Whole Foods combined 8.1%, and Kroger 6.7%.
Costco therefore ranked second in both published comparisons, but the percentages and competitive picture differed. Kroger was third in grocery spending and fourth in the broader CPG measure.
Those figures should not be mixed. Costco’s 8.4% grocery share cannot be compared directly with Kroger’s 6.7% CPG share to describe the gap between their grocery businesses.
The denominator changes, so the meaning changes with it.
Kroger Is Pursuing Its Own Value Strategy
Kroger’s response to competition extends beyond any single market-share report.
In an October 20 investor update, the company outlined plans to make customer value more visible, expand its own-brand products and boost membership, and invest in fresh food and meals.
It also identified e-commerce growth, more direct sourcing and streamlined purchasing as priorities.
Kroger outlined those plans before the market-share comparison received coverage on October 28. Their impact will depend on how the company executes them.
For customers, the relevant question is how those priorities appear in actual prices, product availability, and shopping service, rather than whether a retailer gains or loses one place in a national ranking.
What the Shift Means for Grocery Shoppers
A national spending ranking provides context, not a personalized shopping recommendation.
A household comparing a warehouse club with a supermarket still needs to consider how much it will use, the full cost of the trip, and any membership or delivery charges.
The spending figures do not prove that buying larger packages always saves money, that every Costco item costs less or that a traditional supermarket is a poor choice.
They also do not show that shoppers have abandoned one format entirely. The same household can divide purchases among several retailers.
Costco’s move ahead of Kroger is a measurable change in where grocery dollars are landing. For your own budget, what makes a store worth returning to: the lowest price on a few staples, the convenience of one stop, or the ability to buy exactly what your household needs?
