COST Deep Dive: A very good business, priced for a better one

Two things moved and neither changes the reading. The price rose, so every scenario now sits slightly further below it, and the upside at the most favorable end of the rate band, $741.88, is 30.4% below the 11-09-2026 close. The yield fell, and we have not rebuilt the rate. The stored sensitivities give the scale: on the reference, each percentage point of discount rate is worth about $55.03 a share on the high side of the band and $86.45 on the low side, so a five basis point move is worth about $2.75 to $4.32 a share if all of it passed into the rate, against a $637.60 gap between the reference and the 11-09-2026 close. That is a size for the move and not a new valuation.

What did not move is the evidence the values rest on. In the SEC filing index we read on 11-07-2026, Costco had filed no periodic report since the Form 10-K of 10-07-2026 and no event filing since the Form 8-K of 10-16-2026, and the only later filings were insider transaction reports; we did not read the index again for the 11-09-2026 close. There is no new balance sheet, and the share count and our assumptions are as they were. The one new company document since the valuation is the October sales release, read below. A price about 2.5% higher and a yield five basis points lower leave the gap between price and value where it was, and they give no reason to argue for a different level.

Every break-even moved the way a higher price says it should, and by a small amount: the reference matches the close at a rate of 5.19% instead of 5.24%, which is still below the 20-year and 30-year Treasury yields, and the margin that matches it rises to 7.96%, so FY2036 operating income would have to be 2.55 times the reference's, where it was 2.49 times at the earlier close. The relation between price and value is the one we rated. At the 11-09-2026 close the reference is 59.8% below the price and the upside 44.4% below, and inside the rate band we support no scenario or stress we report reaches it: the closest are the upside's 20-year fade at the band's low rate, $951.66, and the reference's 50-year fade at that rate, $900.95, which are the longest fades we tested for each. The values that do exceed the close are the same ones that exceeded it on 11-02-2026, the upside at a 6.00% rate, $1,276.41, and its 20-year fade at that rate, $1,711.18, and a 6.00% rate is one we do not support. The 11-09-2026 close is 25.4% above the $850.00 low and 2.6% below the $1,094.32 high of the 500 sessions captured to 11-02-2026, so the market record the rating cites is unchanged, and no threshold the report relies on has been crossed.

This is a monthly operating datapoint and not a result. Nine of the 52 weeks of FY2027 are in it, and reported growth is lifted by gasoline prices and currency, as the gap between 11.3% and 7.5% in the nine-week comparable shows. The release reports three different measures, and each answers a different question. Net sales grew 12.8% in the nine weeks, and that includes new warehouses, gasoline prices and currency. Total company comparable sales grew 11.3%, which leaves out new warehouses but keeps gasoline and currency, and 7.5% once gasoline and currency are removed as well. Our reference path assumes net sales growth of 8.0% for the whole of FY2027, a rate that includes new warehouses and everything else in net sales, over 52 weeks and not nine. Because the periods and the definitions differ, the nine-week figures neither confirm nor contradict that assumption: subtracting a short-period comparable rate that excludes new warehouses, gasoline and currency from a full-year total-sales rate would not compare like with like. We have no stored or captured figure for what new warehouses added in these weeks, so we do not build a bridge between the measures. The release also says nothing about capital spending or membership fees, so our $7.5 billion capital intention and our fee growth path are not tested by it. It changes no assumption and moves no value.

These are conditional break-even combinations, not a statement of what investors believe, and a reader can reasonably attribute the gap to a lower rate, a longer high-growth period, or both.

A second lens does not depend on our forecast. FY2026 operating income without the tariff benefit, taxed at 25%, is $8.70 billion of after-tax profit. Capitalized at the central rate with no growth and run through the same bridge, it gives $252.17 a share. That is what the business earns today before any growth; the reference value of $428.58 is what ten years of growth and a growing terminal add to it. At $1,040.55 the market pays 50.1 times FY2026 earnings, for an annualized cash dividend yield of 0.57% at the declared quarterly rate and a free cash flow yield of 2.0%.

The market has also been consistent. Over the 500 sessions to 11-02-2026 that we captured, COST closed between $850.00 and $1,094.32, and the 11-02-2026 close is 17.4% above the first close in that window and 22.4% above the low. Our reference sits 49.6% below even the low. Either the market has paid more than the business was worth for two years, or our framework values this kind of durability too cheaply. We take that second possibility seriously, which is why we develop it as the bull case below.

Two of those rows are about time, and they are the least intuitive. At the central rate, stretching the reference's growth fade from ten explicit years to fifty never reaches the close, and a search to eighty years does not either; at the band's low rate it takes 68 years. Those are the reference's durations; for the upside we tested a 20-year fade only, so a longer upside fade inside the band is untested. The table below shows how the value responds to duration at each of the two rates, and the ladder after it shows the same for the discount rate, where the reference and the upside are each run at illustrative rates inside and outside the band.

Read together, the ladder and the fade say that the rate does most of the work and the duration the rest. A reader who believes the right rate is 6.00% and the right operating case is the upside's holds a view that fits the price, and a reader who believes the rate is 7.65% or above does not, among the durations we tested (the reference's fade to fifty years in the table, the upside's to twenty), unless the reference's growth lasts 68 years at the band's low rate. We do not think the first view is supported by the record, because a 6.00% rate asks for a cost of equity about a point above the government bond on a stock that has ranged between $850.00 and $1,094.32. And we do not rule it out, which is why the beta, premium and spread that build the rate are stated as assumptions.

Put those arguments into the model and the numbers move a long way. The table shows the lenses; none of them is a scenario, and each is conditional on the inputs named.

The pattern in the table is the bull's best argument and its limit. Duration helps but does not reach the price on its own: at the central rate the reference's fade stretched over 30 years is worth $577.51 and over 50 years $690.71, and no length of fade we tried at that rate, up to eighty years, reaches the close; at the band's low rate it takes 68 explicit years of that fade to equal the close, against ten in the model. The discount rate helps more. A 6.00% rate, about a point above the 10-year Treasury yield of 4.91%, values the reference at $785.29, still below the close; it takes the upside's operating case, 2.25% margin, fee growth of 9.5% fading to 6.0%, a 30% terminal return and 3.75% terminal growth, at that rate to give $1,276.41, above the close. At 7.00% the upside is $887.89 and below it. The price, then, fits a world in which the discount rate is within roughly a point of the risk-free rate and the operating results are the upside's, or one in which the rate is nearer 5.24% and the reference is right. Among the combinations we tested inside the discount-rate band we support, 7.65% to 10.31%, with the reference's fade run to fifty years in the table and the upside's to twenty, every value stays below the price, including the generous joint stress of $570.88 and the upside's 20-year fade at the band's low rate, $951.66; a longer upside fade inside the band is untested, and the reference's fade reaches the close at the band's low rate only after 68 years.

What the bull case assumes beyond the record is the discount rate. A 6.00% rate means a cost of equity within about a point of the government bond for a company whose stock has ranged between $850.00 and $1,094.32 in two years and whose sales are tied to consumer spending, tariffs and wages, and it requires beta and the equity premium to be far below the 0.85 and 4.5% we use, neither of which we measured. It also assumes that growth lasts for decades at rates above the economy's, with returns on new capital far above any competitor's we can observe: the club peers earn -0.09% and 1.51% on goods and grow comparable sales slowly, so Costco's result is a product of its scale and execution that a bull must expect to persist rather than something the format guarantees. We take the case seriously, because the market has paid a price like this for two years and we cannot rule out that it is paying for something we undercount. We do not adopt it, because it needs a rate we cannot support and a duration we cannot observe. The evidence that would move us is evidence on those two things: a measured beta and premium that moved the band down, or fee and margin results that keep running ahead of the reference.

The October sales release has reported. The next evidence is the November sales release, expected in early December (the date is not confirmed), and the first-quarter FY2027 report, which last year arrived in mid-December and whose date this year is not confirmed, together with any change to the membership fee. We will compare the fee growth and capital spending in the quarterly report with the reference path above. We make no forecast of the quarter.

Tariffs are a live and unmeasured item. Costco says it paid about $500 million in IEEPA tariffs, received refunds, and expects to reinvest most of them in prices. Four class actions seek to pass refunds through to members, and one court declined to dismiss. The scale of the refunds at issue is known; any exposure from the cases is not, and we do not put a number on it. Costco's wage commitments and California's weight in U.S. sales add operating risk, and the competitive set (Sam's Club in the U.S. and BJ's) is also growing, so none of the evidence we read shows Costco losing share. Finally, the largest risk to a holder at this price is multiple compression. The company's own Form 10-K says, "We believe that the price of our stock currently reflects high market expectations for our future operating results," and a rating this low is a view about that risk.