The Business Behind the Brand (Part 3): Costco (NYSE: COST) — The Warehouse That Prints Money Before It Sells a Single Item

The Arc So Far

This is the final instalment of Arc 1 in our “The Business Behind the Brand” series. In Part 1, we pulled back the curtain on Visa — a company most people think of as a credit card issuer that is actually a toll road on every dollar the world spends. In Part 2, we examined McDonald’s — not a burger chain, but a real estate empire that happens to serve fries. Today, we close the arc with the most personally familiar business model of all — because you’re probably carrying the proof in your wallet right now.

The Model: Profit Before the First Sale

Here’s the number that changes how you think about Costco: 3.01% profit margin.

On trailing twelve-month revenue of $293.59 billion, Costco’s net income is $8.84 billion. That’s a profit margin thinner than most retailers would accept. Woolworths and Coles would baulk at it. Amazon’s retail margins are higher. So why is Costco worth $406 billion?

Because the profit margin on products is deliberately thin. It’s designed to be. Costco doesn’t make money by selling you things at a markup. It makes money by charging you for the privilege of buying things at almost no markup.

The membership fee is the business.

In Q3 FY2026 alone (the 12 weeks ended May 10, 2026), Costco collected $1.37 billion in membership fees — up 10.7% year-on-year. Annualise the run rate and you’re looking at approximately $4.8 to $5 billion in annual membership revenue. That revenue flows through at near-100% margin because there’s virtually no cost of goods associated with it. No inventory to warehouse. No logistics to manage. No shrinkage. Just a fee, collected upfront, before a single item is scanned.

Now compare that to operating income: $11.23 billion (TTM). Membership fee income accounts for roughly 40-45% of operating profit — from revenue that costs almost nothing to generate. The rest of the business — the $293.59 billion in product sales — essentially operates at breakeven to fund the flywheel that keeps members coming back.

This is the Costco model: charge a fee to access low prices → use the fee income as profit → reinvest savings into even lower prices → members renew because prices stay unbeatable. The US renewal rate? ~92-93%. Globally? ~90%. That’s not a subscription — that’s a habit.

The Flywheel in Action: Q3 FY2026

Costco’s most recent quarter (reported May 28, 2026) showed the flywheel spinning faster.

The headline numbers:

• Net sales: $69.15 billion (+11.6% year-on-year from $61.96 billion)
• Total revenue (including membership fees): $70.53 billion — beating consensus estimates of approximately $69.7 to $69.8 billion
• Net income: $2.19 billion (+15% year-on-year from $1.9 billion)
• EPS: $4.93 (in line with LSEG consensus of $4.93; slightly below some estimates of $4.98)
• Adjusted comparable sales: +6.6%
• Digital sales growth: +21%
• Website and app traffic: +37%

The digital growth is worth pausing on. Costco has historically been a “you have to go to the warehouse” business, and the e-commerce channel was a known weakness. A 21% jump in digital sales and 37% increase in traffic suggests the company is finally cracking the online nut without cannibalising the in-store experience that drives impulse purchases and member engagement.

Paid memberships grew 4.1% in the quarter, with executive memberships reaching 41.2 million — these are the higher-tier members who spend more per visit and renew at even higher rates. Total paid members globally now exceed 81 million.

CEO Ron Vachris framed the quarter with characteristic understatement: “Against the backdrop of ongoing macro uncertainty, our focus is providing quality goods and services at the lowest possible price.”

Translation: while other retailers are scrambling to protect margins in a tariff-heavy environment, Costco is leaning into low prices because its margin doesn’t depend on products. The fee does the heavy lifting.

One more number from Q3 that deserves attention: the final five weeks of the quarter were Costco’s top five gas volume weeks ever recorded. Gas stations are Costco’s secret weapon for new member acquisition — first-time members are increasingly being drawn in by fuel savings and then discovering the broader value proposition inside.

Kirkland Signature: The Private Label Moat

Every Costco member knows the Kirkland Signature brand. Fewer understand why it matters to the investment thesis.

Kirkland Signature spans approximately 1,400+ SKUs across food, consumables, clothing, spirits, and electronics accessories. It is estimated to represent 25–30% of merchandise sales in recent periods, carrying meaningfully higher gross margins than national brands. While Costco does not break out exact Kirkland revenue in its filings, the brand’s exclusivity and quality reputation create a second flywheel: members seek out Kirkland, which reinforces membership value and retention.

This creates a competitive moat: you can’t buy Kirkland products anywhere except Costco. Every Kirkland SKU is a reason to maintain your membership. It’s brand loyalty that reinforces membership loyalty — a second flywheel operating inside the first.

The Aussie Angle: Your Informational Edge

Here’s something institutional investors on Wall Street don’t have: the ability to walk a Costco warehouse floor in Melbourne, Sydney, or Canberra and see the model working in real time.

Costco currently operates 15 warehouses across Australia, with an aggressive expansion plan targeting 20 new stores over the next five years. Confirmed openings include Brisbane Airport (expected late 2026), Pakenham in Victoria, and Alkimos in Western Australia (both breaking ground in 2026, opening 2027). Australian e-commerce is live through costco.com.au.

For Aussie investors, this matters in two ways. First, you can physically observe Costco’s model in action — the packed car parks on weekends, the trolleys loaded with bulk purchases, the queues at the petrol station. That’s due diligence you can do in a Saturday afternoon that a fund manager in Manhattan can’t replicate.

Second, Australia represents a meaningful international growth vector. Costco’s US business is mature at 633 warehouses. The real growth optionality lies in markets like Australia, where the warehouse club concept is still relatively novel and the addressable market is underpenetrated. If you’ve noticed your local Costco getting busier, that’s not anecdotal — it’s the thesis playing out.

The FX angle: For Aussie investors, COST brings USD earnings exposure (with 15% US withholding tax on dividends, potentially reduced via W-8BEN) and no franking credits, so it sits naturally alongside currency-hedging considerations in SMSFs or direct portfolios.

The Numbers: Where Costco Stands Today

Trailing Twelve Months (as at July 10, 2026):

Balance sheet:

• Cash and equivalents: $20.00 billion
• Total debt: $8.23 billion
• Net cash: $11.76 billion ($26.53 per share)
• Debt-to-equity: 0.25

The balance sheet is a fortress. Net cash of nearly $12 billion gives Costco enormous flexibility — and they’ve been using it. On April 8, 2026, Costco paid a special dividend of $12.00 per share, totalling $5.3 billion returned to shareholders. The regular annual dividend sits at $5.88 per share (0.64% yield), growing at 12.60% year-on-year.

An ROIC of 38.44% deserves emphasis. For every dollar of capital Costco invests in the business, it generates 38 cents in return. That’s exceptional capital allocation in any sector, let alone retail.

Valuation: The Bull and Bear Case

Let’s be honest about where the stock sits.

Price: $916.25 (July 10, 2026 close)
Trailing P/E: 45.92
Forward P/E: 41.72
PEG ratio: 4.25
EV/EBITDA: 28.47

Costco trades at a significant premium to the market. A trailing P/E of nearly 46x means investors are paying roughly 46 years’ worth of current earnings for each share. The forward P/E of 41.72 prices in healthy earnings growth, but the PEG ratio of 4.25 suggests the stock is expensive even after adjusting for that growth.

The bull case: Analysts remain overwhelmingly positive. The consensus target from 37 analysts is $1,080.33, implying approximately 17.95% upside from the current price. Oppenheimer has a $1,160 target (Outperform, raised May 19, 2026), and Goldman Sachs sits at $1,159 (Buy, raised May 29, 2026). The argument: Costco’s membership flywheel is one of the most durable competitive advantages in retail, and the combination of pricing power, international expansion, and digital acceleration justifies a premium multiple. The tariff normalisation following the Supreme Court’s invalidation of certain Trump administration tariffs on foreign imports is a tangible tailwind — Costco’s Asia-sourced supply chain benefits directly, and management has stated they’ll return tariff refund savings to members “in some form.”

The bear case: At these multiples, there is no margin for error. The stock is down 6.73% over 52 weeks and trades below both its 50-day moving average ($985.49) and 200-day moving average ($956.81). The RSI sits at 36.00 — approaching oversold territory. Costco’s 3% profit margin means any operational hiccup — supply chain disruption, a failed international expansion, or a membership growth slowdown — hits the bottom line disproportionately hard. Amazon’s continued expansion of grocery delivery and the Walmart+ membership programme put competitive pressure on the membership model itself. And at a beta of 0.87, the stock isn’t even offering above-market volatility to compensate for the premium you’re paying.

Sam’s Club (Walmart) raised its membership fees on May 1, 2026 — Club tier from $50 to $60, Plus tier from $110 to $120. This is the first increase in 3.5 years. On one hand, it validates the membership model and Costco’s pricing power. On the other, it signals that competitors are willing to invest in their own membership ecosystems.

The competitive landscape in US warehouse clubs:

Costco’s dominance is clear, but 63.7% market share also means future US growth requires either taking share from weaker competitors or growing the overall pie.

The Verdict

Costco is one of the highest-quality businesses in global retail. The membership flywheel is genuinely difficult to replicate, the balance sheet is pristine, capital allocation is excellent, and the Australian expansion gives local investors a tangible connection to the thesis.

But quality has a price — and right now, that price is steep. At 42 to 46 times earnings with a PEG of 4.25, the stock is priced for flawless execution in a world where geopolitical shocks, tariff uncertainty, and competitive pressure make flawless execution anything but guaranteed.

For existing holders, the thesis is intact. For prospective buyers, the question isn’t whether Costco is a great business — it clearly is. The question is whether $916.25 is a great price. The RSI and moving average signals suggest the market is still working through that question.

The Arc Closes

Over three weeks, we’ve peeled back three businesses every Australian recognises. Visa showed us the invisible toll road inside every tap-and-go payment. McDonald’s revealed the real estate empire underneath the Golden Arches. And Costco exposed the membership machine that generates profit before a single item is sold.

The common thread: the business you see isn’t the business you own. The real value — the durable, compounding, moat-protected value — lives in the model underneath.

Next week, we begin a new arc. Three companies connected by the most studied investor in history, starting with the stock he says he’ll never sell.

Data Sources:

• Costco Q3 FY2026 Earnings Release (28 May 2026) – investor.costco.com
• Latest 10-Q filing
• LSEG / Yahoo Finance consensus and analyst targets (Oppenheimer, Goldman Sachs notes)
• Company announcements and local reporting for Australian warehouse expansion and renewal rates (often discussed in earnings calls or 10-K)
• Macrotrends / company financials for TTM reconciliation

Wall St. Down Under | Australia

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