⚠ Every Marketplace Sale Is a Sale Walmart Did Not MakeModerate threat

Walmart (WMT) — threat to the moat

A commission is lovely money and less money than a gross margin, and Walmart does not disclose the split between addition and substitution.

A marketplace commission is lovely money and it is less money than a retail margin, and the difference is the part of this story nobody emphasises.

Growth in the June 2026 quarter, year on year (%)Marketplace sales+52%Walmart Connect (U.S.)+43%Total advertising+38%Global eCommerce+23%Total revenue+5.9%Walmart Q2 FY2027 earnings release and presentation
Third-party sales are growing more than twice as fast as eCommerce as a whole, so they now drive most of the online growth. Walmart does not say how much of that is new assortment and how much is sales it would otherwise have made itself.

When Walmart sells its own inventory it earns the full gross margin — 24.2% of net sales at the company level in fiscal 20261. When a third-party seller makes the same sale on Walmart's site, Walmart earns a commission and, if the seller uses Walmart Fulfillment Services, a fee. That total is high-margin and it is smaller in absolute dollars on most baskets than owning the sale would be.

So the growth is genuinely good and genuinely ambiguous. Marketplace sales rose 52% in the June 2026 quarter against 23% for eCommerce as a whole2. Some of that is pure addition — items Walmart would never have stocked. Some of it is substitution — a customer buying a third-party listing of something the store carries. Walmart does not disclose the split, and the split is the whole question.

The second cost is control. Walmart's proposition rests on the customer not having to evaluate the seller: the price is fair, the product is what it says, and the return is easy. A marketplace imports counterfeit exposure, variable service and quality dispersion into a brand built on the opposite.

The third is that marketplace inventory sits outside the store estate, which is Walmart's main structural advantage. Growth here is growth in the part of the business where Walmart competes with Amazon on Amazon's terms.

Watch marketplace growth against first-party eCommerce growth. Walmart does not report it directly; the observable proxy is the gap between marketplace at 52% and total eCommerce at 23%3, which says the third-party half is now doing most of the work.

References
  1. Moat Explorer calcWhen Walmart sells its own inventory it earns the full gross margin — 24.2% of net sales at the company level in fiscal 2026.
    Moat Explorer calculation from figures in Walmart's own filings: global eCommerce of about $150.4 billion (Walmart U.S. $99.6B + International $35.8B + Sam's Club $15.0B) against $120.9 billion, a $29.5 billion increase against a $31,875M rise in net sales ($706,413M against $674,538M), about 92%; Walmart U.S. selling floor of 698.7 million square feet (633,724 + 36,609 + 28,375 thousand) and net sales per store of $104.7 million ($482,975M over 4,611 stores); operating margin 4.18% ($29,825M/$713,163M) against 4.31% ($27,012M/$648,125M); net margin 3.07%; gross profit rate 24.2% ($171,018M/$706,413M); grocery 59.1% of Walmart U.S. net sales ($285,482M/$482,975M) against 59.8% ($264,210M/$441,817M) and grocery growth of 3.4%; general merchandise to grocery ratio 0.40 against 0.43; health and wellness +26.7% ($54,898M to $69,547M); payables less inventories $4,210M ($63,061M less $58,851M); rent 0.34% of revenue ($2,434M/$713,163M); capital expenditure 64% of operating cash flow ($26,642M/$41,565M); a 1% overrun on $147,943M of expense is $1,479M; eCommerce penetration 27.5% international ($35.8B/$130,423M) and 20.6% at Walmart U.S. ($99.6B/$482,975M); shareholder returns $15,587M ($7,507M dividends plus $8,080M repurchases) against $14,923M of free cash flow; Q2 FY2027 net income attributable down 9.4% ($6,366M against $7,026M); Walmart U.S. comparable sales of about 3.9% excluding the 125 basis point pharmacy headwind — FY2024-Q2 FY2027 · publ. September 2026 · source ↗
  2. ReportedMarketplace sales rose 52% in the June 2026 quarter against 23% for eCommerce as a whole.
    Walmart second-quarter fiscal 2027 earnings presentation (Form 8-K exhibit 99.2) - Walmart U.S. comp sales +2.6% with transactions excluding fuel +1.5% and average ticket excluding fuel +1.1% against total like-for-like inflation of 1.4%, and an approximately 125 basis point pharmacy headwind from maximum fair price regulation; eCommerce +24% including approximately 43% growth in store-fulfilled delivery, total advertising +38% including Walmart Connect +43%, and Marketplace sales +52%; expedited deliveries under three hours approximately 37% of store-fulfilled orders; share gains across categories and income tiers led by upper-income households — Q2 FY2027 · publ. August 20, 2026 · source ↗
  3. ReportedWalmart does not report it directly; the observable proxy is the gap between marketplace at 52% and total eCommerce at 23%, which says the third-party half is now doing most of the work.
    Walmart second-quarter fiscal 2027 earnings presentation (Form 8-K exhibit 99.2) - Walmart U.S. comp sales +2.6% with transactions excluding fuel +1.5% and average ticket excluding fuel +1.1% against total like-for-like inflation of 1.4%, and an approximately 125 basis point pharmacy headwind from maximum fair price regulation; eCommerce +24% including approximately 43% growth in store-fulfilled delivery, total advertising +38% including Walmart Connect +43%, and Marketplace sales +52%; expedited deliveries under three hours approximately 37% of store-fulfilled orders; share gains across categories and income tiers led by upper-income households — Q2 FY2027 · publ. August 20, 2026 · source ↗
Sources
Generated September 22, 2026