Most companies keep investors guessing until earnings day.

Costco doesn’t. Because the warehouse club reports sales every month, investors walking into Thursday’s fiscal fourth-quarter release already know most of the top line. The quarter ended August 30^th, and the company published its sales figures in early September.

That changes what matters. When Costco announces its full quarterly results after the close on Thursday, the headline revenue number will be close to a formality. The questions that will move the stock are about membership, margins and the quality of earnings — and on at least one of those, there’s a genuine debate among analysts.

What We Already Know

The sales picture is strong. Fourth-quarter net sales reached $93.9 billion, up 11.3% from $84.4 billion a year ago, and full-year fiscal 2026 net sales came in at $297.3 billion, up 10.2%. Total company comparable sales rose 9.4% for the quarter, led by an impressive 10.7% gain in the U.S., with Canada up 5.0% and other international markets up 7.0%. Digitally enabled comparable sales climbed 19.5%.

Costco now operates 939 warehouses worldwide, including 647 in the U.S. and Puerto Rico. By region, the company pointed to the Southeast, San Diego and the Midwest as its strongest U.S. markets, with Spain, China and Korea leading internationally.

The Gasoline Asterisk

Those headline comps deserve one qualification. Strip out the effects of gasoline prices and foreign exchange, and total company comparable sales rose 6.7% for the quarter — a gap of roughly 270 basis points versus the reported figure.

With oil prices surging past $100 a barrel this summer, pricier fuel inflated reported sales. That’s not a problem, but it matters for interpretation: gasoline is a traffic driver for Costco, not a profit center, and it carries thin margins. The 6.7% adjusted figure is the better measure of underlying health — and it’s still excellent, modestly ahead of the 6.4% posted in the year-ago quarter. Growth is holding up, not decelerating.

What’s Expected Thursday

Consensus calls for earnings of roughly $6.48 per share, up about 10.4% from $5.87 a year ago, on revenue of approximately $94.82 billion, up 10%. That revenue figure includes membership fees on top of the $93.9 billion in net sales already disclosed. For the full fiscal year, analysts expect earnings near $20.42 per share, up 13.5%.

Costco carries a Zacks Rank #3 (Hold), which suggests shares are likely to perform roughly in line with the broader market in the near term. The track record is steady: Costco has beaten consensus earnings in each of its last five quarters. It has rarely delivered large surprises, which is part of why the stock tends not to move dramatically on earnings.

Membership Is the Number That Matters

If there’s one metric to watch Thursday, it’s the membership renewal rate.

Membership fees are Costco’s quiet engine. The company prices merchandise with thin markups to drive traffic, then earns a substantial share of its operating profit from annual fees. Renewal rates are therefore the clearest signal of whether that model is working.

The recent trend has been a mild but persistent drift lower. The U.S. and Canada renewal rate stood at 93.0% in the second quarter of fiscal 2025, then steadily eased to 92.1% over the following quarters. Management has attributed much of the decline to the growing share of members who sign up online, who historically renew at somewhat lower rates than those who join in a warehouse.

The encouraging sign came last quarter, when the rate ticked back up to 92.2% — the first hint of stabilization after several quarters of decline. Thursday’s figure will show whether that was a blip or the start of a floor. A reading at or above 92.2% would ease the most persistent concern hanging over the stock.

The Tariff Refund Question

Here’s where the debate gets interesting. Like Walmart and Target, Costco (COST Quick QuoteCOST - Free Report) has been receiving refunds of IEEPA tariffs following the Supreme Court’s February decision striking them down. Costco has been passing much of that benefit back to members through price cuts on items like eggs, cheese, coffee, textiles, bedding and cookware — consistent with CEO Ron Vachris’s philosophy of being “first to lower prices and last to raise them.”

Across retail earnings this season, refund benefits have repeatedly flattered reported profits, and investors have learned to look through them. Any explicit disclosure of Costco’s refund benefit — and how much it contributed to the quarter — will shape how the market reads the headline number.

Margins bear watching as well. Costco’s third-quarter gross margin came in at 11.04%, down 21 basis points but up 1 basis point excluding gasoline. With fuel, transportation and food costs rising into September, the cost environment for the new fiscal year has become more challenging.

Costco shares have slipped about 4.5% over the past month, underperforming the S&P 500, and trade about 17% below their May peak. Even after that pullback, the stock still trades near 40 times forward earnings, a premium valuation that leaves little room for disappointment.

Image Source: StockCharts

Bottom Line

Costco enters Thursday with the hard part already done: an 11.3% sales gain, a 6.7% underlying comp, and nearly 20% digital growth are all on the record. What investors will be grading is the quality beneath those numbers.

Three things matter. Does the renewal rate hold at or above 92.2%, confirming stabilization? How much did tariff refunds contribute to earnings, and does the business clear consensus without them? And what does management say about the cost environment heading into fiscal 2027?

A Zacks Rank #3 (Hold) captures the setup fairly. This is one of the highest-quality businesses in retail, executing well in a difficult environment — but at 40 times forward earnings, quality is already priced in.