Costco vs. Sam's Club in 2026: A Comparative Analysis of the U.S. Club Market

On April 8, 2026, Costco Wholesale Corporation paid its members a $12-per-share special dividend — a $5.3 billion cash return that, in another retail sub-segment, would have been read as a defensive maneuver. In Costco's case, it was a victory lap. Three weeks later, on May 1, 2026, Sam's Club raised its base membership fee for the first time in three and a half years, lifting Club from $50 to $60 and Plus from $110 to $120. Inside an 18-month window, the two largest U.S. warehouse clubs both repriced their core products — and both saw membership counts continue to climb.

That is the headline state of an industry that has quietly become one of the most defensible corners of American retail. While department stores contract, drug chains restructure, and dollar stores chase a moving margin floor, warehouse clubs are growing comparable sales in the high single digits, opening more locations than at any point in the last decade, and trading at the highest valuation multiples in the consumer-staples universe. Costco closed fiscal 2025 with $269.9 billion in net sales and 81 million paid memberships; Sam's Club closed its fiscal year a few months earlier at $90.2 billion. The two operators run virtually identical-format boxes — roughly 140,000 square feet, narrow assortments around 4,000 to 6,000 SKUs, membership-gated, treasure-hunt merchandising — yet they earn very different returns per square foot and serve very different households.

This analysis decomposes the two competitors across nine dimensions: market context, financial performance, membership economics, real estate footprint and trade-area mechanics, operational and strategic positioning, customer demographics, competitive threats, investment and lending implications, and the strategic outlook through 2030. It draws on Costco's FY2025 10-K and Q2 FY2026 8-K filings, Walmart's segment disclosures, the MMCG database (industry data referenced from IBISWorld and Warehouse Club Focus, recalibrated against company filings), Numerator panel data, and net-lease cap-rate observations from Boulder Group and CRE Daily. It is intended as a working reference for shopping-center developers, retail real estate investors, SBA-financed adjacent-retail borrowers, and lenders evaluating warehouse-club-anchored projects. Readers familiar with our prior comparative work — Macy's vs. Nordstrom and CVS Health vs. Walgreens — will recognize the format. The conclusions, in this case, are sharper than either of those.

1. Market Context: A Concentrated Channel Outgrowing the Rest of Retail

The Warehouse Clubs and Supercenters industry, defined under NAICS 45291, is forecast to generate approximately $770.4 billion in U.S. revenue in 2026, a 1.6 percent gain over an estimated $758 billion in 2025 (MMCG database). The five-year compound annual growth rate has run at 2.1 to 2.9 percent, decelerating from the inflation-amplified 5.5 percent growth observed in the 2021 to 2024 window. That headline number, however, is a poor proxy for the warehouse club business itself, because it bundles Walmart Supercenters, Target SuperTargets, and Meijer-style operators into the same statistical bucket as Costco, Sam's Club, and BJ's.

Stripping the supercenters out, the pure warehouse club sub-segment is meaningfully smaller and meaningfully faster-growing. Warehouse Club Focus, the trade publication that tracks the four U.S./North American operators (BJ's, Costco, PriceSmart, and Sam's Club), reported combined club sales of $382.9 billion in 2023, $431 billion in 2024 (a 12.6 percent year-over-year jump), and an MMCG-estimated $465 billion to $475 billion in 2025. The U.S.-only club channel is dominated by three players.

Exhibit 1.1 — U.S. Warehouse Club Channel: Sizing and Share, 2025E

Operator	U.S. Club Revenue (2025E)	U.S. Club Count	U.S. Market Share
Costco (incl. Puerto Rico)	≈ $197 billion	633	63.7%
Sam's Club	$90.2 billion	600	29.2%
BJ's Wholesale Club	≈ $21.5 billion	247	7.0%
U.S. Warehouse Club Total	≈ $308.7 billion	1,480	100%

Source: Costco 10-K FY2025; Walmart 10-K FY2025; BJ's company disclosures; Warehouse Club Focus; MMCG database.

A CR3 ratio of effectively 100 percent and a Herfindahl-Hirschman Index above 5,000 place the warehouse club channel among the most concentrated retail sub-segments in the U.S. economy. That concentration is functional: the three-operator structure has held since BJ's emerged from a Zayre Corporation spinoff in 1997, and the cost of building a competitive warehouse club from scratch — purchase volume, member trust, supply-chain depth — has effectively closed the door on new entrants. The MMCG database registers only 16 reporting warehouse club and supercenter enterprises in the United States in 2025, up from 15 in 2024.

Why the channel keeps gaining share

Three forces have anchored warehouse clubs' outperformance through the post-pandemic period. The first is persistent food and household-goods inflation, which has converted upper-middle-class and middle-class households into systematic bulk buyers; both Costco and Sam's Club called out grocery and health-and-wellness share gains throughout fiscal 2025 and the first half of fiscal 2026, with Sam's Club specifically citing Circana data showing share gains in groceries and general merchandise. The second is the breadth of membership penetration — 56 percent of U.S. consumers now hold at least one warehouse club membership per Mintel, and Numerator's 2024 panel found 46 percent of households shopped Costco at least once and 43 percent shopped Sam's Club. Younger cohorts (23 percent of Generation Z, 17 percent of Millennials) represent the largest greenfield opportunity. The third is tariff hedging: both operators' purchase-volume leverage has insulated members from much of the 2025 to 2026 tariff regime, and Costco CEO Ron Vachris committed in March 2026 to return any recovered tariff charges to members through lower prices.

On the back of these forces, MMCG's forward base case calls for the U.S. warehouse club sub-segment to grow at a 4.5 to 5.5 percent compound annual rate through 2030 — materially faster than the 2.1 percent forecast for the broader supercenter-inclusive industry. The next decade of growth will be a function of Costco's international engine, Sam's Club's tech-led repositioning, and the build cycle both operators have entered.

2. Financial Performance: Two Engines, Different RPMs

The single most striking feature of any side-by-side Costco vs. Sam's Club analysis is that the two retailers operate nearly the same number of U.S. boxes — 633 versus 600 — but Costco generates roughly 2.0 times the U.S. revenue per warehouse. That gap has been remarkably stable for more than a decade. It is the structural fact that drives every other comparison in this report.

Costco's fiscal 2025 (ended August 31, 2025) closed at $269.9 billion in net sales, up 8 percent year-over-year, with $5.32 billion in membership fee revenue (up 10 percent), $8.13 billion in net income, and diluted EPS of $18.21. The first quarter of fiscal 2026 added another $65.98 billion in net sales (up 8.2 percent), and Q2 FY2026 (the 12 weeks ended February 15, 2026) reached $68.24 billion in net sales (up 9.1 percent) with EPS of $4.58 (up 13.9 percent) and digitally-enabled comparable sales growth of 22.6 percent. Membership fee revenue in Q2 FY2026 climbed 13.6 percent to $1.355 billion.

Sam's Club, the membership-club segment of Walmart Inc., posted $90.2 billion in fiscal 2025 net sales (year ended January 31, 2025) and $2.4 billion in segment operating income, up 9.7 percent year-over-year despite a roughly 730 basis-point headwind from lapping the prior year's LIFO benefit. Q3 fiscal 2026 (13 weeks ended November 2, 2025) reached $23.5 billion in net sales (up 3.1 percent) and comp sales of 5.2 percent excluding fuel, with double-digit transaction growth and double-digit membership-fee growth — the fifth consecutive quarter of double-digit fee gains for the Walmart subsidiary.

Exhibit 2.1 — Comparative Financial Snapshot, Most Recent Reporting Periods

Metric	Costco (FY25, ended 8/31/25)	Sam's Club (FY25, ended 1/31/25)	Latest Quarter
Net sales	$269.9 billion	$90.2 billion	Costco Q2 FY26: $68.24B
Membership fee revenue	$5.32 billion	Not separately disclosed	Costco Q2 FY26: $1.355B
Operating income	≈ $10.5 billion	$2.4 billion	Costco Q2 FY26: $2.74B
Net income	$8.13 billion	n/a (segment)	Costco Q2 FY26: $2.04B
Comparable sales (ex-fuel/FX)	+5.9%	+5.9%	Costco +6.7% / Sam's +5.2%
Operating margin	≈ 3.9%	≈ 2.7%	Costco Q2 FY26: 3.95%
Gross margin	≈ 12.9%	Not disclosed	Costco Q2 FY26: 12.88%
New clubs opened (period)	27 (incl. 3 relocations)	8 in TTM through Q2 FY26	Costco Q2 FY26: 4 new

Source: Costco Form 10-K FY2025 and Form 8-K Q2 FY2026 (filed March 5, 2026); Walmart Form 10-K FY2025 and Q3 FY2026 earnings presentation. n/a indicates segment-level rather than entity-level disclosure.

Productivity: where Costco's lead becomes structural

On a U.S. revenue-per-warehouse basis, Costco generated roughly $311 million per club in fiscal 2025 (calculated as approximately $197 billion in U.S. sales divided by 633 U.S. warehouses). Sam's Club generated approximately $150 million per club ($90.2 billion across 600 clubs). Newer Costco vintages are even more productive: warehouses opened in fiscal 2025 generated $192 million in annualized first-year sales, up from $150 million two years earlier — meaning a brand-new Costco now matches the average existing Sam's Club inside its first twelve months of operation.

On a sales-per-square-foot basis, the gap is similar. Costco runs at approximately $1,700 to $1,800 per square foot of warehouse space across its average 147,000-square-foot box. Sam's Club runs at approximately $1,100 per square foot across its 134,000-square-foot box. Both are multiples of typical big-box productivity (a Walmart Supercenter generates roughly $430 to $650 per square foot; the average U.S. supermarket runs near $520). Warehouse clubs are, by a wide margin, the highest-productivity freestanding anchor format in U.S. brick-and-mortar retail.

This productivity gap is not an artifact of category mix or geography. It is a function of three structural advantages. Costco members spend roughly twice as much per visit as Sam's Club members ($96 versus $79 per Numerator's 2024 panel), they visit more frequently (32 trips per year versus 20), and they skew toward higher-income households that bring a larger share-of-stock-up wallet. The cumulative effect — a Costco member spends an average of $3,086 per year versus $1,583 at Sam's Club — is what drives the per-warehouse gap, not square footage or assortment differences.

3. Membership Economics: The Fee Engine

The single most defensible asset in either operator's P&L is the annual membership fee. It is paid in advance, recognized over twelve months, costs essentially nothing to deliver, and flows almost directly to operating income. For Costco, fee income alone covers a meaningful share of total operating income: $5.32 billion in fee revenue against $10.5 billion in operating income in fiscal 2025 means roughly half of Costco's profit is generated before a single product is sold. The retail business operates, in effect, as a high-volume break-even engine that exists to justify the fee.

Costco ended Q2 fiscal 2026 with 81.4 million paid memberships worldwide, up from 81.0 million at the close of fiscal 2025 (Q4 FY25 paid count grew 6.3 percent year-over-year). Executive members — the $130 premium tier that earns 2 percent back up to $1,250 annually — totaled 39.7 million, representing 48.8 percent of the paid base and generating 74.2 percent of worldwide net sales in fiscal 2025. Total cardholders, which include household card add-ons, reached 105.9 million. The September 1, 2024 fee increase — Gold Star from $60 to $65, Executive from $120 to $130, with the rewards cap rising from $1,000 to $1,250 — was Costco's first base-fee adjustment since 2017 and added an estimated $400 million to high-margin fee income on a steady-state basis.

Sam's Club does not publicly disclose its total member count, but the company has confirmed all-time-high membership at every consecutive quarter through fiscal 2025 and into fiscal 2026. Plus tier penetration — Sam's Club's $120 premium product, comparable to Costco's Executive tier — climbed approximately 300 basis points in fiscal 2025 and another 180 to 320 basis points in early fiscal 2026. The May 1, 2026 fee increase, the first since October 2022, raises Club from $50 to $60 and Plus from $110 to $120, while lifting the Plus 2 percent Sam's Cash cap from $500 to $750. MMCG estimates Sam's Club holds approximately 60 to 65 million U.S. paid members, triangulated from disclosed fee revenue growth and competitor disclosures.

Exhibit 3.1 — Membership Economics, Side-by-Side

Metric	Costco	Sam's Club
Base membership fee	$65 (Gold Star)	$60 (Club, eff. May 1, 2026; was $50)
Premium tier fee	$130 (Executive)	$120 (Plus, eff. May 1, 2026; was $110)
2% rewards cap	$1,250 (raised from $1,000)	$750 (raised from $500)
Last fee increase	September 1, 2024 (7-year gap)	May 1, 2026 (3.5-year gap)
Paid members (latest)	81.4 million worldwide	Not disclosed; ≈ 60–65M U.S. (MMCG est.)
U.S./Canada renewal rate	92.1%	≈ 90% (MMCG est.; not disclosed)
Worldwide renewal rate	89.7%	n/d
Premium tier penetration	48.8% (Executive)	≈ 45% (Plus; MMCG est.)
Avg. annual member spend	$3,086	$1,583
Avg. trips per year	32	20

Source: Costco Form 10-K FY2025; Costco Q2 FY2026 8-K; Walmart investor disclosures; Numerator panel 2024; MMCG database. Renewal rates as of Q2 FY2026 quarter end.

The renewal rate signal investors are watching

Costco's worldwide renewal rate has compressed modestly from a peak near 90.5 percent in mid-fiscal 2024 to 89.7 percent at the close of Q2 fiscal 2026. The U.S. and Canada rate has fallen from 93.1 percent to 92.1 percent across the same window. Those declines are small in absolute terms, but they are unprecedented in Costco's modern history, and they have drawn attention from the sell-side. Costco management's explanation — that a higher mix of online sign-ups, including the December 2023 Groupon promotional cohort, renews at slightly lower auto-renew rates than warehouse-acquired members — is plausible and supported by the 50 percent share of new sign-ups that are now under 40 years old. If management is correct, the compression is a long-term positive masquerading as a near-term metric softening. If not, it is the first crack in the most cited moat in U.S. retail.

The fee engine is not sensitive to retail-business performance. It is sensitive to whether members continue to value the membership. That makes the renewal rate the single most important number on either retailer's earnings page.

4. Real Estate Footprint and Trade-Area Mechanics

For developers, brokers, and lenders, the Costco vs. Sam's Club question is rarely a head-to-head competition for the same site. Both retailers select sites that the other would not bid for. Understanding why — and how the trade-area mechanics differ — is the difference between a feasibility study that supports financing and one that does not.

Footprint specifications

A typical Costco warehouse occupies 146,000 to 147,000 square feet of building footprint on 14 to 18 acres of land. A typical Sam's Club is slightly smaller, at 134,000 to 136,000 square feet on 13 to 17 acres. Both formats include attached gas stations at most locations (574-plus Costco fuel stations; the majority of Sam's Club sites also feature fuel), and both require generous parking ratios — Costco at 6.5 to 7.5 stalls per 1,000 square feet of gross leasable area, Sam's Club slightly tighter at 5.5 to 6.5 stalls per 1,000. Costco's largest U.S. warehouse, in Salt Lake City, Utah, runs 235,000 square feet; the smallest, in Juneau, Alaska, is just 76,696 square feet. Sam's Club's largest unit, in Pineville, North Carolina, reaches 185,000 square feet.

Exhibit 4.1 — Real Estate Footprint and Trade-Area Comparison

Specification	Costco	Sam's Club
U.S. club count (early 2026)	633 (incl. Puerto Rico)	600
Average building footprint	146,000–147,000 sq ft	134,000–136,000 sq ft
Largest U.S. unit	235,000 sq ft (Salt Lake City)	185,000 sq ft (Pineville, NC)
Smallest U.S. unit	76,696 sq ft (Juneau, AK)	≈ 32,000 sq ft floor (rare)
Typical land area	14–18 acres; up to 22 acres	13–17 acres
Parking ratio	6.5–7.5 stalls per 1,000 sq ft	5.5–6.5 stalls per 1,000 sq ft
Trade-area population (10-mi)	200,000–400,000 typical	100,000–250,000 typical
Median household income target	$90,000+ (Executive sites $110K+)	$60,000–$80,000
SKU count	≈ 3,800–4,000	≈ 5,000–6,000
Real estate strategy	Owned majority (>80% U.S.)	Owned majority; minority NNN
Largest state (warehouses)	California: 143–144	Texas: ≈ 82

Source: Costco Form 10-K FY2025; Walmart Form 10-K FY2025; ScrapeHero location databases; Triple Net Investment Group property comps; MMCG database.

Site selection: who wins which trade area

Costco's site selection criteria target high-density, high-income suburban and urban-edge locations. The company favors trade-area populations of 200,000 to 400,000 within a ten-mile drive, with a strong preference for primary-trade-area median household incomes north of $90,000. In saturated metros — Los Angeles, San Francisco Bay Area, New York metro, Seattle — Costco has gone so far as to operate multiple warehouses within five-mile radii, accepting cannibalization to capture share. California alone holds 143 to 144 of Costco's 633 U.S. warehouses, or about 22.6 percent of the U.S. fleet, followed by Texas (42 to 44), Washington (33 to 35), Florida (approximately 34), Illinois, New Jersey, and Arizona. Costco does not currently operate in West Virginia, Wyoming, or Rhode Island.

Sam's Club's site selection extends further into secondary and tertiary markets. The company targets trade-area populations of 100,000 to 250,000 within a ten-mile drive and median household incomes of $60,000 to $80,000, with willingness to pull customers from 25-minute drive times in rural and small-MSA contexts. Texas leads the Sam's Club fleet at approximately 82 clubs. Sam's Club has zero locations in Alaska, Massachusetts, Oregon, Rhode Island, Washington State, or Vermont — a footprint that is broadly the inverse of Costco's strongest geographies. Numerator panel data confirms that Sam's Club indexes meaningfully higher in rural and small-MSA households than Costco does. For a deeper read on Costco's geographic distribution and per-state productivity, see our prior research on Costco Wholesale's U.S. operations in 2025.

Anchor-tenant economics for shopping center developers

Both operators carry investment-grade credit profiles — Costco at A+ from S&P, Walmart at AA — placing them among the most lender-favored anchors in U.S. retail. For a shopping-center developer underwriting a project anchored by either club, the structural reality is that the anchor itself is rarely on the rent roll. Both companies favor build-to-suit ownership of their boxes, with the anchor parcel delivered as part of a master ground-up development and the developer monetizing inline GLA, junior anchors, and pad sites as the income-producing portion of the asset.

The distinction matters in three ways. First, Placer.ai foot-traffic data shows Costco generates approximately 50 percent more visits per location and roughly twice the spend per visit of Sam's Club, which translates directly into higher inline tenant sales and supportable rent. Second, the income skew of Costco's trade area pulls higher-end inline and pad tenants — banks, premium QSR, specialty fitness, urgent care — at a rate Sam's Club centers do not match. Third, lease structures, when they exist, are typically 20- to 25-year initial terms with five 5-year options, NNN, with corporate guarantees; Sam's Club is the more prevalent NNN and ground-lease tenant in the secondary market because Walmart has historically been more comfortable monetizing its real estate.

MMCG's underwriting database tracks outparcel rents adjacent to a Costco at 10 to 25 percent premiums versus comparable Sam's Club outparcels in the same MSA, reflecting the higher household income skew and higher visit-to-spend conversion. For developers structuring shopping center feasibility studies or evaluating whether a project pencils with one anchor versus the other, that delta is the single most consequential underwriting variable.

5. Operational and Strategic Comparison

Assortment and the private-label engine

Both retailers run intentionally narrow assortments. Costco carries approximately 3,800 to 4,000 SKUs; Sam's Club carries approximately 5,000 to 6,000. A conventional supermarket carries 30,000 or more, and a full-line Walmart Supercenter carries upwards of 100,000. The narrow SKU count is the operational engine of the warehouse club model. Each SKU at Costco averages multiple-million-dollar annual sell-through, generating supplier leverage that drives the 11 to 15 percent gross-margin model and that no general-merchandise retailer can replicate.

Private-label penetration is the second engine. Costco's Kirkland Signature, founded in 1995, generates approximately 28 percent of net sales by the company's own disclosure (third-party estimates including co-branded and gas-station Kirkland sales place the figure as high as 33 percent). Costco caps Kirkland gross margins at 15 percent — a deliberate constraint that protects the value perception and compounds member loyalty. Sam's Club's Member's Mark, consolidated in 2017 from more than 20 prior labels, generates an estimated 30 percent of segment sales across a broader 600-plus SKU base. Member's Mark has been Walmart's most aggressive private-label investment of the past five years, with new product launches, in-club tastings, and what Sam's Club CEO Chris Nicholas has framed as a direct attempt to "take down" Kirkland in member preference.

Technology: where Sam's Club has structurally caught up

On in-club technology and digital infrastructure, Sam's Club has moved past Costco — and by a non-trivial margin. Sam's Club's Scan & Go mobile checkout has reached more than 50 percent transaction penetration; the Grapevine, Texas store launched in October 2024 operates with no traditional checkout lanes at all, a pure Scan & Go format that Walmart intends to roll out to additional clubs. AI-powered receipt verification was deployed chain-wide to all 600 U.S. clubs in April 2025. Sam's Club's e-commerce contributed approximately 17 percent of ex-fuel sales by Q1 fiscal 2026, with quarterly e-commerce growth running at 22 to 39 percent throughout fiscal 2025 and fiscal 2026. The American Customer Satisfaction Index Retail and Consumer Shipping Study 2025 ranked Sam's Club above Costco for the first time, driven by the Scan & Go experience.

Costco's digital adoption has been deliberately slower. The company has not adopted Scan & Go, citing shrink-control and member-experience concerns, and e-commerce sits at approximately 9 percent of total net sales. That said, digitally-enabled comparable sales rose 22.6 percent in Q2 fiscal 2026 — accelerating, not flat — and Costco's CFO has signaled increased technology investment is on the road map. Whether the company chooses to follow Sam's Club into Scan & Go or builds a different digital architecture will be one of the most consequential strategic decisions of the next three years.

Workforce and wages

Costco's wage structure is the most expensive in U.S. mass retail. Under the three-year employee agreement that took effect in March 2025, top-of-scale clerks now earn $31.90 per hour, top-of-scale assistants earn $30.20 per hour, the wage floor sits at $20 per hour, and the average U.S. and Canadian hourly wage exceeds $31. Costco is partially unionized — Teamsters represent warehouses in California, New York, New Jersey, Maryland, Virginia, and Washington — but the same pay structure applies across union and non-union locations. Sam's Club wages, in line with Walmart's national $17.50 wage floor, run approximately $14 to $18 per hour for store-level staff. The implied SG&A headwind for Costco is roughly 120 to 180 basis points of operating margin, yet Costco still posts higher operating margins (3.9 percent versus 2.7 percent), evidence of the membership-fee leverage on the P&L.

Ancillary services and the Costco moat

Both retailers operate gas stations, pharmacies, optical, hearing aids, tire centers, and food courts. Costco's ancillary footprint is the more comprehensive: food courts in 604 of its U.S. warehouses, optical in 603, pharmacy in 603, gas stations in 574-plus, and tire centers in 600. Costco Travel and the Costco Auto Buying Program generate meaningful ancillary revenue. Sam's Club's mix is similar but smaller in scale per club; the company has, however, invested heavily in food-court innovation, including a 2025 menu refresh designed explicitly to compete with Costco's $1.50 hot dog and rotisserie chicken anchors.

6. Customer Demographics and Cross-Shopping Behavior

The single demographic fact that explains nearly every other gap in this analysis is income. Costco's median member household income runs approximately $110,000 to $125,000 — Numerator and Northwestern's Spiegel Center place the Costco income index at 130 against a 100 baseline for the average U.S. household. Sam's Club's median member household income runs approximately $75,000 to $80,000, indexed slightly above the U.S. average but materially below Costco. That $35,000 to $45,000 income gap, multiplied across tens of millions of households, drives the trip-frequency, basket-size, and spend-per-year differentials that show up in financial performance.

On geographic skew, Costco indexes higher in urban, dense suburban, and West Coast markets, with particular strength among Asian-American households (nearly twice the index of the average U.S. retail household). Sam's Club indexes higher in rural and small-MSA markets and is slightly favored by Black and Hispanic and Latino households per Numerator. Both index strongly with families and Generation X. Sam's Club skews slightly older overall, though Costco is increasingly attracting a younger member — approximately 50 percent of new Costco sign-ups in fiscal 2025 and fiscal 2026 to date are under 40 years old, an age-cohort shift that mirrors what mmcginvest.com has tracked in adjacent middle-class consumer categories.

The Amazon Prime overlap

Cross-shopping data tells a more nuanced story than the warehouse club versus warehouse club framing would suggest. Per Northwestern's 2024 Spiegel Research panel, 35.2 percent of Amazon Prime members also hold a Costco membership, while 22.2 percent of Prime members hold a Walmart+ membership. Among adult U.S. respondents, 28.2 percent are Costco members, 16.8 percent are Walmart+ members, and 58.2 percent are Amazon Prime members. The implication is direct: Amazon Prime, at $139 per year, is the de facto functional substitute for warehouse club membership in any household that values shipping speed over bulk savings. The competitive set for Costco and Sam's Club is no longer just the other club. It is Amazon Prime.

7. Competitive Threats: Aldi, Amazon, and the Hard Discounters

Three structural threats sit on the warehouse-club horizon. None is fatal in the next three years; all are shaping capital allocation today.

Threat #1 — Hard discount grocery

Aldi US announced a five-year, $9 billion, 800-store expansion plan in 2024 and is on a trajectory to operate approximately 3,200 stores by year-end 2028, up from approximately 2,474 stores in early 2026. Aldi's grocery-basket pricing benchmarks closely matched Sam's Club's lowest-price reads in Warehouse Club Focus's 96-item September 2024 basket — eroding warehouse clubs' grocery price leadership for non-bulk shoppers. Aldi's exclusive private-label model, with approximately 90 percent of its mix under store brands, directly challenges the Member's Mark and Kirkland value story. Aldi pressures Sam's Club more than Costco: the Sam's Club $76,000-MHI member base overlaps materially with Aldi's target demographic, while Costco's $125,000-MHI member base is largely insulated. This asymmetric exposure is one of the reasons Walmart is funding the 600-club Sam's Club remodel and the 15-clubs-per-year build cadence — the company is reinforcing the format before Aldi takes meaningful share of the value-shopper trip.

Threat #2 — Amazon Prime as functional membership

Amazon Prime competes for the same household-budget membership wallet as Costco's Gold Star or Sam's Club's Club tier. The bundled value of Prime — free shipping, streaming, Whole Foods discounts, music, photos — is, on a strict cost-of-membership basis, larger than either warehouse club's offer. Bernstein's 2025 retail framework named Amazon, Walmart, and Costco as the best-positioned operators to ride a macroeconomic storm, precisely because of membership-driven customer lock-in. The risk is not that Amazon will replace Costco in a household's wallet today; it is that Amazon will erode the share-of-trip a club captures from any given household over a five- to ten-year horizon.

Threat #3 — E-commerce grocery

Costco's grocery business is materially under-indexed online relative to Sam's Club's. Sam's Club captures over 50 percent of member transactions through digital channels including in-club Scan & Go; Costco's grocery is heavily routed through Instacart, leaking margin and customer relationship to a third-party logistics platform. If Amazon, Kroger, Walmart, or Instacart materially win share-of-stock-up trips over the next three to five years, Costco's per-warehouse productivity is exposed in a way Sam's Club's is not. Costco has signaled increased internal grocery delivery investment, but the gap with Sam's Club is real and growing.

8. Investment, Lending, and Real Estate Implications

For shopping-center developers, retail real estate investors, and SBA-financed adjacent retailers, the operational and financial differences between Costco and Sam's Club translate into measurable underwriting variables. The two anchors are not interchangeable in a credit memo, and treating them as such is one of the most common forms of mispriced risk MMCG sees in feasibility-study scope work.

Cap rates and trade comps

The single-tenant net-lease retail market entered a holding pattern in late 2025 and early 2026 after nine consecutive quarters of cap-rate expansion. The national average single-tenant net-lease retail cap rate sat at approximately 6.57 percent in Q3 2025, slightly compressed from a 6.96 percent Q1 2025 peak. Within that market, investment-grade warehouse-club anchors trade at meaningfully tighter cap rates than the average.

Exhibit 8.1 — Cap Rate Reference Table, Q1 2026 (MMCG database)

Asset Type	Typical Cap Rate Range
Costco fee-simple sale-leaseback	5.75% – 6.25%
Costco ground lease (corporate guarantee)	5.00% – 5.75%
Sam's Club fee-simple NNN	6.25% – 6.75%
Sam's Club ground lease (Walmart corp.)	6.00% – 6.50%
Costco-anchored shopping center inline	7.00% – 7.75%
Sam's Club-anchored shopping center inline	7.25% – 8.00%
QSR ground lease on Costco outparcel	4.50% – 5.50%
QSR ground lease on Sam's Club outparcel	5.25% – 6.25%

Source: Boulder Group net lease research; CRE Daily; MMCG database. Cap rates reflect institutional-quality assets with 15+ years of remaining lease term and corporate guarantees.

SBA 7(a) and 504 implications for adjacent retail

For SBA 7(a) and SBA 504 borrowers acquiring or developing on parcels adjacent to a warehouse club anchor, the underwriting implications are concrete. Lenders consistently underwrite 5 to 10 percent lower first-year sales-risk premiums for tenants within 0.25 miles of a Costco anchor versus comparable un-anchored locations. Sam's Club proximity carries a similar but slightly less aggressive underwriting benefit. CDC lenders working USDA-zone properties tend to ascribe meaningful demonstrated trade-area demand to Sam's Club locations specifically, given Sam's Club's stronger rural and small-MSA penetration. For borrowers structuring SBA 7(a) and 504 feasibility studies for QSR, urgent care, dental, fitness, automotive, or specialty service tenants on outparcels, anchor selection is a meaningful risk-pricing variable, not a stylistic one. The MMCG SBA / USDA loan comparison calculator walks borrowers through the loan-program implications of these underwriting differences.

The build cycle: 100+ new pads in the next three years

The most actionable real estate implication is the build cycle itself. Costco plans 28 net new warehouses in fiscal 2026, supported by a $6.0 billion to $6.5 billion capex envelope, including five relocations, depot expansion, remodels, and digital infrastructure. Sam's Club has committed to 15 new clubs per year and a full remodel of all 600 existing clubs to the Grapevine, Texas "club of the future" standard. Together, these programs imply more than 100 new U.S. warehouse-club pad sites coming to market in the 2025 through 2028 window — the most aggressive build cycle in the channel's history. For developers with land assemblage in markets that fit either operator's site selection criteria, the deal pipeline for outparcel and sub-anchor opportunities will be at its largest in over a decade.

9. Strategic Outlook 2026–2030: Who Wins on What Dimension

The strategic outlook for the U.S. warehouse club channel through 2030 is not a binary Costco-or-Sam's-Club question. It is a dimension-by-dimension competitive read in which each operator has carved out a structural advantage that the other is unlikely to close in a five-year horizon.

Exhibit 9.1 — 2026–2030 Forecast: Likely Winner by Strategic Dimension

Strategic Dimension	Likely Leader 2026–2030	Rationale
Per-club revenue productivity	Costco	2× lead, embedded in member affluence; not closeable by Sam's
Membership renewal rate	Costco	92%+ U.S./Canada vs. ≈ 88–90% est. Sam's
E-commerce growth rate	Sam's Club	Walmart fulfillment + Scan & Go scaling faster
New club opening velocity	Sam's Club	15/yr new + 600 remodels vs. ≈ 17 net new U.S. for Costco
Total revenue growth	Costco	International + new U.S. + fee leverage
International expansion	Costco	Sam's Club is U.S.-only
Wage and ESG leadership	Costco	Industry-leading wages, Teamsters relationship
Tech-driven margin expansion	Sam's Club	AI receipt verification, register-less stores
Real estate developer demand	Costco	Higher-income trade area, lower cap rates

Source: MMCG database; company filings; analyst consensus.

Costco's international engine

Costco operated 924 warehouses across 14 countries by early 2026: 634 in the U.S. and Puerto Rico, 114 in Canada, 42 in Mexico, 37 in Japan, 29 in the United Kingdom, 20 in Korea, 15 in Australia, 14 in Taiwan, seven in China, five in Spain, three in France, two in Sweden, and one each in Iceland and New Zealand. International comparable-sales growth ran at 9.5 percent in Other International and 7 percent in Canada in early fiscal 2026, materially ahead of U.S. comp growth of approximately 6 percent. The Mulhouse, France opening in Q1 fiscal 2026, the July 2025 Malmö, Sweden launch, the June 2025 Pyeongtaek, Korea opening, and the planned 200,000-plus square foot Monterrey, Mexico flagship for 2026 mark a continued aggressive international build cadence that Sam's Club, by structure, cannot match. Walmart operates in international markets, but Sam's Club itself is a U.S.-only banner.

Sam's Club's tech-forward repositioning

At its 2025 Investment Community Meeting, Sam's Club announced a target of doubling membership and more than doubling sales and profit over an eight- to ten-year horizon. The strategy rests on three pillars: 15 new clubs per year (versus the prior cadence of approximately three per year), a full remodel of all 600 existing clubs to the Grapevine standard, and deepening integration with Walmart's enterprise digital and fulfillment infrastructure. The Q3 fiscal 2026 results — fifth consecutive quarter of double-digit membership-fee growth, double-digit transaction growth, plus continued Plus-tier penetration gains — suggest the strategy is in motion.

Costco's valuation overhang

Costco's stock closed at approximately $994 per share in late April 2026, with a market capitalization between $441 billion and $448 billion, a trailing P/E of 51.7 times, a forward P/E near 47 times, and an EV/EBITDA of 30.8 to 32.4 times — roughly 50 to 60 percent above the company's ten-year median EV/EBITDA of 21.3 times and approximately 263 percent above the Retail-Defensive industry median of 8.6 times. Costco shares outperformed the S&P 500 by 20 percentage points year-to-date through early March 2026, and the company paid a $5.3 billion / $12 special dividend in April 2026 — the third such special dividend in seven years. The valuation is the single largest investment risk in the Costco thesis. It is supported by structural advantages and a defensive growth profile, but it leaves little margin for execution missteps. Walmart, which carries Sam's Club inside the consolidated entity, trades at a more conventional 38 times forward earnings.

Working with MMCG on Warehouse Club–Adjacent Real Estate

MMCG Invest, LLC is a national commercial real estate feasibility consulting firm with deep expertise in warehouse-club-anchored shopping centers, retail feasibility studies, outparcel underwriting, and SBA 7(a) and 504 feasibility deliverables for adjacent-retail borrowers. The firm holds Appraisal Institute Practicing Affiliate status and has produced third-party feasibility studies for SBA, USDA Business and Industry, and conventional lenders across hospitality, multifamily, retail, industrial, gas station, and specialty-use asset classes. For developers, investors, or lenders evaluating a Costco-anchored or Sam's Club-anchored project — or a retail outparcel or junior-anchor opportunity adjacent to either — MMCG's analytical methodology draws on CoStar, Placer.ai, AirDNA, Numerator, and proprietary trade-area benchmarks to deliver lender-acceptance-ready deliverables. Reach out to MMCG to discuss study scope, timeline, and pricing.

April 30, 2026 by Michal Mohelsky, J.D.

MMCG Invest, LLC is feasibility study consultant that provides independent, third-party feasibility studies for SBA and USDA guaranteed loan programs across all commercial real estate asset classes, including multifamily, hotel, industrial, retail, self-storage, senior living, and mixed-use properties. Our studies incorporate absorption rate analysis, lease-up modeling, pre-stabilization cash flow bridging, pro forma and scenario-based stress testing to meet the analytical rigor required by leading government-guaranteed lenders, CDCs, and institutional investors. For more information, contact our team directly.

Evaluating a development or acquisition that requires defensible absorption assumptions? Reach out to discuss how our methodology supports your lending decision.

Michal Mohelsky, J.D. | Principal | mmcginvest.com 

Contact: michal@mmcginvest.com

Phone: (628) 225-1125

Disclaimer: This report is provided for informational purposes only and does not constitute investment advice. Data presented herein is derived from proprietary MMCG databases and third-party sources believed to be reliable; however, MMCG Invest makes no representation as to the accuracy or completeness of such information. Figures from third-party industry databases have been independently verified and, where appropriate, adjusted to reflect MMCG's proprietary analytical methodology. Past performance is not indicative of future results.

Sources

(1) Costco Wholesale Corporation, Form 10-K for fiscal year ended August 31, 2025, filed October 8, 2025 (SEC EDGAR).

(2) Costco Wholesale Corporation, Form 8-K, Q2 fiscal 2026 earnings release, filed March 5, 2026 (SEC EDGAR).

(3) Costco Wholesale Corporation, Form 8-K, Q1 fiscal 2026 earnings release, filed December 11, 2025 (SEC EDGAR).

(4) Walmart Inc., Form 10-K for fiscal year ended January 31, 2025, filed March 14, 2025 (SEC EDGAR).

(5) Walmart Inc., Q3 fiscal 2026 earnings release and presentation, November 2025 (Walmart Investor Relations).

(6) Sam's Club, 2025 Investment Community Meeting press release, April 11, 2025 (Walmart Corporate).

(7) MMCG database, derived from IBISWorld, Warehouse Clubs & Supercenters in the US Industry Report (NAICS 45291), 2025 edition, recalibrated against company filings.

(8) Warehouse Club Focus, U.S. and International Warehouse Club Sales 2023–2024 (industry trade publication).

(9) Mintel, US Warehouse Clubs Market Report, 2025 edition.

(10) Kentley Insights, Warehouse Clubs & Supercenters US Industry Market Research Report, 2025 edition.

(11) Numerator, Warehouse Club Demographic and Spend Panel, 2024 release.

(12) Northwestern University, Spiegel Research Center, U.S. Membership Cross-Shopping Panel, 2024 edition.

(13) Boulder Group, Net Lease Sam's Club Property Profile and Cap Rates, 2025 update.

(14) CRE Daily, Net Lease Cap Rate Steady, Q3 2025 brief.

(15) Commercial Property Executive, 2024 Net Lease Sales Volume and Cap Rates summary.

(16) Placer.ai, Warehouse Club Visit Trends Q1 2024 and FY2025 reports.

(17) Kantar Retail IQ, Sam's Club Q3 2025 and Q4 2025 commentary.

(18) Stocktitan and Last10K SEC filings aggregator, COST and WMT filings index, accessed April 2026.

(19) AlphaSpread and StockAnalysis, COST market capitalization and valuation data, April 2026.

(20) GuruFocus, COST EV-to-EBITDA historical series, accessed April 2026.

(21) FinancialContent, "Costco's $5.3 Billion Victory Lap: The Anatomy of the $12 Special Dividend," April 8, 2026.

(22) TheStreet, Sam's Club membership fee increase coverage, April 2026.

(23) TheStreet, Costco accelerated warehouse expansion strategy, March 2026.

(24) Fortune, Costco hourly wage agreement coverage, March 11, 2025.

(25) American Customer Satisfaction Index, Retail and Consumer Shipping Study 2025.

This report has been prepared by MMCG Invest, LLC for informational purposes. It does not constitute investment advice, a solicitation, or an underwriting opinion. Industry data referenced as "MMCG database" reflects MMCG's recalibration of third-party sources against direct company disclosures.