Eighty-Two Million, and Not One That MattersWide moat

Costco Wholesale (COST) — moat facet

Diversified by name and correlated by circumstance — no customer can hurt Costco and one recession can reach all of them.

Costco's filings disclose no customer accounting for a material share of revenue, because none does. At the third quarter of fiscal 2026 there were 82.9 million paid memberships and 148.5 million total cardholders1, up from 79.6 million and 142.8 million a year earlier. Fiscal 2025 closed at 81.0 million paid — 68.3 million Gold Star and 12.7 million Business including affiliates — with 64.2 million free household cards attached2.

Memberships and cardholders (millions)79.6mPaid, Q3 FY202582.9mPaid, Q3 FY2026142.8mCardholders, Q3 FY2025148.5mCardholders, Q3 FY2026Paid memberships rose 3.3 million in twelve months.
No customer can hurt Costco and no customer can negotiate with it. The price is on a sign and a member either pays it or does not.

The direct benefit is that no negotiation is possible. A supplier with a large customer accepts terms; Costco's price is posted on a sign and a member either pays it or does not. There is no discount schedule, no annual rebate, no key-account manager, and no counterparty capable of demanding one. Compare that with almost every other company in this collection, where a handful of buyers set the terms.

The credit benefit is equally clean. Members pay at the till in cash, debit or Visa credit, and pay their annual fee in advance. Costco carries essentially no customer receivable; the $3,750 million on the balance sheet is vendor and insurer money3. A retailer with no customer credit exposure is a retailer that cannot be hurt by a customer's bankruptcy, only by a customer's mood.

The limitation is correlation. These are not 82.9 million independent bets. They are overwhelmingly North American households — the United States and Canada are 86% of net sales, and California alone is 26% of American net sales4 — exposed together to employment, fuel prices, mortgage rates and grocery inflation. Costco's diversification protects it against the loss of any customer and not at all against the loss of a customer type.

Set paid memberships against the renewal rate. Both rising is health. Membership growth continuing while renewal drifts down would mean the base is being refilled faster than it leaks, which is the pattern that precedes a plateau.

Moat trajectory: Widening

82.9 million paid memberships from 79.6 million, and 148.5 million cardholders from 142.8 million. There is still no customer worth naming, and there are more of them.

The number that tests this moat
Reported
Paid memberships and total cardholders
82.9 million and 148.5 million at the third quarter of fiscal 2026

Membership growth continuing while the renewal rate drifts down would mean the base is being refilled faster than it leaks — the pattern that precedes a plateau.

Source: Costco Form 10-Q, quarter ended May 10, 2026 ↗
References
  1. ReportedAt the third quarter of fiscal 2026 there were 82.9 million paid memberships and 148.5 million total cardholders, up from 79.6 million and 142.8 million a year earlier.
    Costco Form 10-Q, quarter ended May 10, 2026 - MD&A (comparable sales +10% and +7% excluding fuel and currency, ticket +7% against frequency +2%, membership fees $1,373M, renewal 92.2% and 89.7%, gross margin 11.04%) — Q3 FY2026 and the first 36 weeks · publ. June 3, 2026 · source ↗
  2. ReportedFiscal 2025 closed at 81.0 million paid — 68.3 million Gold Star and 12.7 million Business including affiliates — with 64.2 million free household cards attached.
    Costco Form 10-K, fiscal year ended August 31, 2025 - Item 1 Business (membership counts and renewal rates, warehouse and gas-station counts, under 4,000 SKUs, Executive tier and the 2% reward, human capital and wages, competition, Kirkland Signature) — FY2025 · publ. October 8, 2025 · source ↗
  3. ReportedCostco carries essentially no customer receivable; the $3,750 million on the balance sheet is vendor and insurer money.
    Costco Form 10-Q, quarter ended May 10, 2026 - condensed financial statements and notes (total revenue $70,527M, operating income $2,815M, diluted EPS $4.93, balance sheet, segment table, 928 warehouses) — Q3 FY2026 and the first 36 weeks · publ. June 3, 2026 · source ↗
  4. ReportedThey are overwhelmingly North American households — the United States and Canada are 86% of net sales, and California alone is 26% of American net sales — exposed together to employment, fuel prices, mortgage rates and grocery inflation.
    Costco Form 10-K, fiscal year ended August 31, 2025 - Item 1A Risk Factors (U.S. and Canada 86% of net sales and 84% of operating income, California 26% of U.S. net sales, cannibalisation, tariffs, supplier and site-acquisition risk, 'high market expectations') — FY2025 · publ. October 8, 2025 · source ↗
Sources
Generated September 23, 2026