Costco earnings preview: Can strong sales justify COST stock’s valuation?

Costco offers shoppers a reason to pay less. Its shareholders face a different question: how much should they pay for that business? With fourth-quarter sales already disclosed, this earnings report is less about proving that customers are shopping and more about whether membership income, margins and cash generation can justify the stock’s demanding valuation.

Let’s break down what is already known about Costco’s quarter, what the earnings release still needs to reveal and how investors can judge whether stronger profits are enough to support COST stock.

Our assessment is that the business enters the report with a stronger case than a simple “consumer slowdown” narrative suggests. The harder argument is valuation: dependable demand deserves recognition, but it does not protect shareholders from paying too much for each dollar of earnings.

When will Costco report earnings and what does Wall Street expect?

Costco’s investor-relations calendar lists its Q4 FY2026 earnings results for September 24 at 1:15 p.m. Pacific Time. That is after the regular US stock-market session and falls early the following morning in India.

Sources: Costco Q4 FY2026 event calendar; Costco August 2026 sales release; Barron’s pre-results article, “Costco Earnings May Disappoint, but There’s a Special Catalyst That Could Lift the Stock”; Costco FY2025 results.

The expected earnings level is roughly 12% above the prior-year figure. However, analyst estimates can change and adjusted estimates need to be reconciled with reported diluted EPS when results arrive. A small beat is less informative if it comes from a tax benefit rather than better operating performance.

Costco’s fiscal fourth quarter is longer than its third quarter. Comparing the two quarters’ absolute revenue without accounting for the different number of weeks would exaggerate sequential growth. The appropriate starting comparison is the corresponding prior-year quarter.

What do Costco’s reported Q4 sales already tell investors?

Costco has already published the quarter’s merchandise sales and comparable-sales performance. Those figures should be treated as known information rather than potential earnings-day surprises.

Source: Costco August sales release, September 2, 2026. “Adjusted” here excludes gasoline-price and foreign-exchange effects.

The adjusted figures show that growth extends beyond fuel prices and currency translation. However, the gap between reported and adjusted growth also explains why investors should not treat every additional dollar of sales as evidence of equivalent growth in shopping volumes.

Two distinctions matter. Net sales exclude membership fees, so they are not identical to total revenue. Adjusted comparable sales also remain a dollar-sales measure: removing gasoline-price and currency effects does not remove inflation from every product category.

August’s adjusted company comparable-sales growth was 5.4%. Costco said the later timing of Labor Day reduced August total and comparable sales growth by slightly less than 75 basis points. That makes a slowdown inferred from one month less clear-cut than the headline suggests. The calendar effect should not be mechanically applied to the entire quarter.

The analytical priority now shifts from demand to profit conversion. Investors already know that sales grew; the report needs to show what remained after merchandise costs, wages, logistics and other operating expenses.

Why are membership growth and renewals central to Costco’s outlook?

Memberships encourage customers to return and give Costco a recurring revenue stream alongside merchandise sales. But membership-fee growth can come from several sources: additional members, upgrades, higher fees and currency movements. Those drivers have different implications for future growth.

Source: Costco Q3 FY2026 earnings call, May 28, 2026, transcript published by The Motley Fool.

These figures describe the membership base at the end of Q3, not the upcoming Q4 result. The central question is whether Costco is retaining existing households while adding enough new members to sustain future spending.

Management said Q3 membership income grew 7% after excluding the fee increase and currency effects. That gives investors a useful underlying benchmark. Fee income rising faster than the member count is not automatically a concern if upgrades are driving the difference, but persistent member-growth weakness would eventually limit the pool of future shoppers.

The fee increase that took effect in September 2024 raised US and Canadian standard annual fees to $65 and Executive fees to $130 in their respective local currencies. That is an existing change, not a new catalyst to count again. As its incremental contribution matures, new members and upgrades become more important to the growth story.

Membership revenue should not be described as pure profit. The membership proposition depends on competitive prices, service and operating investment. Nor is dividing fee revenue by net income a valid calculation of the percentage of profit generated by memberships: one figure is revenue before costs and the other is profit after costs and tax.

For this report, a reassuring outcome would combine steady retention with continued member growth and upgrades. Higher fee income accompanied by deteriorating retention would deserve closer scrutiny, even if the quarter’s EPS exceeds expectations.

Can Costco convert sales growth into stronger profit margins?

A high-volume retailer can produce a meaningful earnings change from a very small movement in its margins. Costco’s latest completed quarter provides a useful baseline.

Source: Costco Q3 FY2026 consolidated results. Operating margins are author calculations using operating income divided by total revenue.

Profit grew, but the operating margin was broadly unchanged. That distinction matters: EPS growth alone does not establish that the core retail operation became substantially more profitable per dollar of revenue.

Investors should separate changes in merchandise profitability from changes in expenses relative to sales. They should also examine product mix. A larger share of sales from a lower-margin category can reduce the overall margin even when individual categories are performing sensibly.

A simple calculation shows why apparently tiny movements deserve attention.

Source: Author scenario using reported Q4 net sales. The tax rate and rounded share count are assumptions, not forecasts. The model assumes other factors are unchanged.

A tenth of a percentage point of sales can therefore represent a material part of a small earnings beat or miss. The calculation does not predict a margin change; it explains why wages, freight, inventory accounting and pricing decisions can matter more than another strong sales headline.

Tariffs and input costs deserve the same earnings-quality check. Management discussed tariff-refund claims on the Q3 call and indicated that amounts previously passed to customers could be returned to members in some form. Any subsequent recovery should be examined for its accounting treatment and associated customer commitments before being treated as a recurring profit improvement.

Our preference when assessing this report would be for durable operating improvements supported by member demand. A short-term margin increase achieved by weakening Costco’s value proposition would be less reassuring than stable margins accompanied by healthy retention and growth.

What are investors paying for COST stock before earnings?

The distinction between business quality and investment value is especially important here. Costco’s recurring customer relationships can justify a premium, but the price still embeds assumptions about how long earnings will grow and how much investors will pay for them.

Sources: INDmoney’s timestamped Costco quote; Costco FY2025 and Q3 FY2026 results. Trailing EPS calculation: $18.21 − $12.34 + $14.01. Small differences from data-provider ratios can arise from rounding, share counts or update timing. The reference quote is not represented as an official closing price.

At that reference price, investors are paying roughly $45.50 for each dollar of trailing annual earnings. This is a calculated trailing ratio, not a forward P/E based on analyst forecasts. The distinction avoids giving an apparently cheaper forward multiple without explaining the earnings assumptions behind it.

Readers can follow the Costco share price separately as the market moves. The valuation model below deliberately fixes the reference price so that the relationship between earnings growth and the P/E remains visible.

Source: Author calculations using the approximate $19.88 trailing EPS base. Hypothetical scenarios, not analyst targets or forecasts. Prices are rounded and exclude dividends.

The middle row illustrates the risk clearly. Earnings can rise 12% while a valuation of 40 times those earnings produces a price below the reference quote. At 45 times earnings, the same business growth produces a substantially different result.

The multiples are sensitivity assumptions rather than claims about a correct valuation. Their purpose is to show that a promising company can produce disappointing shareholder returns if the market reduces its premium. Conversely, a sustained premium can support returns when the business keeps delivering.

Our view is that an earnings beat should strengthen the case for future cash generation before it is used to justify a higher valuation. A few additional cents of quarterly EPS are not, by themselves, evidence that investors should pay more for every future dollar of profit.

Can cash flow and a special dividend strengthen the investment case?

Costco’s cash position gives it flexibility, but investors should distinguish financial capacity from a board decision to distribute money.

Source: Costco Q3 FY2026 consolidated financial statements. Free cash flow is calculated as operating cash flow less additions to property and equipment; it is an author-defined measure.

These figures support the argument that growth is producing cash as well as accounting earnings. However, working-capital movements can influence cash flow and a cash balance is not entirely surplus cash. The business still needs liquidity for inventory, supplier payments, investment and other obligations.

Costco declared a $15-per-share special dividend in December 2023, payable in January 2024. That historical payment explains why investors discuss another distribution. It does not establish the timing or amount of a future one.

A special dividend transfers cash from the company to shareholders. It does not create an equivalent amount of new operating value and the share price generally adjusts for the distribution around the ex-dividend date, alongside other market movements.

The more durable question is whether Costco can keep funding expansion while generating excess cash. A dividend announcement could influence the immediate reaction, but it would not resolve weak retention or deteriorating operating economics if those appeared elsewhere in the report.

Can digital growth and warehouse expansion support the next phase?

The most useful digital question is whether easier shopping increases profitable customer spending. Faster online growth is encouraging only if it creates additional business or improves retention without an excessive fulfilment burden.

Costco is a retailer with a growing digital channel, not a software company simply because some transactions happen online. Investors should look for evidence that technology improves convenience, inventory availability or operating efficiency. A higher digital sales share does not automatically warrant a technology-sector valuation.

Warehouse expansion requires a similar distinction between activity and returns. A new location can add members and sales, but opening costs, staffing and the time required to build local demand affect its contribution. Management’s discussion of new-store productivity is therefore more informative than an opening count alone.

For international operations, local-currency demand matters more than a favourable translation into dollars. Expansion can widen the future customer base, but overseas success should be assessed through repeat visits, retention and returns on the money invested rather than geography alone.

Management’s comments about the coming year also matter because Costco does not provide conventional earnings guidance. Investors should look for concrete operating expectations, including the timing of openings and investment priorities, rather than assume the call will supply a formal EPS target. Management confirmed its approach to guidance during the Q3 earnings call.

The broader lesson is that growth must be evaluated after its cost. More locations and more online orders strengthen the investment case when they create durable cash flow per share.

What should investors watch in Costco’s earnings release?

The report should be assessed as a set of connected indicators rather than a single EPS number. The following framework separates stronger evidence from outcomes that need more explanation.

A constructive report would connect membership health with consistent operating profits and cash generation. A mixed report could contain strong EPS but insufficient evidence that growth is becoming more durable. A weaker outcome would raise questions about the customer relationship or the cost of sustaining it, even if total sales still look impressive.

Costco’s value proposition may attract households trying to stretch their budgets. That makes it relevant to investors studying consumer staples stocks, but resilience in customer demand should not be confused with immunity from share-price volatility.

Its results also provide a useful consumer-spending signal for investors following the S&P 500. However, one membership retailer is not a complete proxy for every US household or retail category. Company-specific execution can improve even when other businesses struggle.

For Indian investors, the dollar share return is only one part of the outcome. Currency changes also affect returns measured in rupees. That makes valuation discipline and a suitable holding period more useful than reacting solely to the first move after the earnings release.

Costco earnings preview: Our assessment of the valuation risk

Costco’s sales disclosure provides a credible starting point for a healthy earnings report. The investment case now needs evidence that the customer relationship remains strong and that growth continues to produce cash after the spending required to sustain it.

The valuation creates a tougher test. A business can remain excellent while its shares deliver modest returns if the market reduces the amount it is willing to pay for earnings. The scenario analysis shows why operational success and share-price performance should be assessed separately.

Our stance is that membership quality and repeatable profit conversion deserve more weight than a small EPS surprise or speculation about a special dividend. Results that support those two foundations would reinforce Costco’s long-term business case. They would still need to be weighed against the price investors are paying for that quality.