KAISER ALUMINUM CORP (KALU) stock intrinsic value fair value estimate & owner earnings analysis

Kaiser Aluminum rolls and extrudes aluminum into plate, sheet, coil and extruded shapes for four markets: aerospace and high-strength plate (Trentwood, Washington), beverage and food can stock (the Warrick, Indiana mill bought from Alcoa in 2021), general engineering products sold largely through metal service centers, and automotive extrusions. The cost of the aluminum itself is passed through to customers, so the business really earns a conversion fee; in 2025 net sales were $3.37 billion but conversion revenue was only $1.45 billion. Five customers took about 56% of 2025 sales and the largest took 16%, mostly under multi-year supply agreements. Earnings level. We measure the cash the owners keep: operating cash flow with working-capital swings and stock pay removed, less the capital spending needed to keep the plants running. Because metal prices whip inventories and receivables around, the working-capital adjustment matters enormously here: 2025 operating cash flow of $111 million hid a $168 million metal-driven working-capital build. On that basis owner earnings per share were $6.22 (2021), -$1.51 (2022), $2.30 (2023), $1.67 (2024) and $8.39 (2025); before interest the business produced roughly $9.30, $1.37, $5.02, $4.15 and $11.41 a share. We measure from the Warrick acquisition onward, because the earlier, smaller aerospace-and-extrusion company is a different business. That window is distorted at both ends: 2022-2024 carry the heavy Warrick coating-line and Trentwood expansion spending, which we treat as upkeep because revenue fell with metal prices, so those years are understated; 2021 is flattered because the revenue jump from the acquisition swamps upkeep spending; and 2025 includes about $93 million of favorable metal price lag, a windfall from rising aluminum prices that reverses when prices fall. Netting these out, we judge the business's normal pre-interest cash generation at about $6.00 a share, close to the window median of $5.02 lifted modestly for the expansion spending now finished (2026 capital spending is guided to $120-130 million versus $181 million in 2024). Strong first-half 2026 results (net income of $159 million) owe much to elevated US aluminum prices and premiums, so we do not lift the level on them. 2025's growth rate was far above anything we assume; year one of the base case is set below 2025, not above it. Debt. The company owes $550 million of 4.50% notes due 2031 and $500 million of 5.875% notes due 2034 (issued in 2025 to replace notes due 2028), plus about $15 million of finance leases, against $58.5 million of cash at June 30, 2026, with the revolving credit line essentially undrawn. The cheap 2031 notes are worth a small credit, leaving net debt of about $971 million, roughly $57 a share. Retiree medical obligations are paid in cash each year and are already charged in owner earnings. Base case. Pre-interest cash generation of $5.75 a share next year as metal price lag fades, then about $6.00 a share sustained, with no growth credited. The new Warrick coating capacity and Trentwood plate capacity are built, but filling them depends on demand and share gains that are not yet in hand, so they are left out. The business is worth about $1.69 billion ($100 a share); after $971 million of debt, the shares are worth about $42. Bear case. One full aluminum and end-market downturn of the kind the company actually lived through in 2020, when pandemic aerospace destocking cut pre-interest cash generation by about half (from $9.97 to $5.20 a share), and again in 2022 when destocking and metal swings drove it to $1.37. We model $4.50 next year, two trough years at $2.00 and $1.50, a recovery through year five, and $4.50 thereafter as the cost of the packaging-heavy Warrick mix and the 56% customer concentration weighs on margins. In the two trough years cash generation falls below the roughly $50 million interest bill, which the company's liquidity (about $547 million of cash plus credit availability at the end of 2025) can bridge, and the first note maturity is not until 2031. The business is worth about $1.16 billion ($69 a share) against $971 million of debt, leaving about $11 a share. Leverage is the reason a moderate business setback becomes a severe hit to the shares. Bull case. The company's own levers deliver: the finished expansion lifts pre-interest cash generation to $7.00 next year, rising to about $9.00 a share as the new capacity fills, roughly the 2019 aerospace-cycle peak level ($9.97) on a larger asset base. The business is worth about $2.48 billion ($147 a share); after debt the shares are worth about $89. Margin-of-safety price. We are only moderately sure of the earnings level: the past five years show no two alike, every one is bent by metal prices, expansion spending or acquisition effects, and our $6.00 normal figure is a judgement rather than an observed run rate. The worst plausible outcome is a long downturn in commercial aerospace together with the loss or repricing of a major packaging contract, which with roughly $1 billion of debt could leave the shares worth little; the assets are hard and the debt does not mature until 2031 and 2034, so the company should survive, but shareholders would bear nearly all the loss. If we are wrong about the normal level by a dollar a share, the shares move by about $17; if the expansion never earns its keep, the base case is roughly right but no better. During the holding period, the company pays $3.08 a share in dividends, a meaningful cushion. The margin-of-safety price is $30: from that price, recovering to the base value of about $42 over roughly three years plus about $9 of dividends implies about 20% a year, and the bear case leaves most of the dividend stream intact while preserving the business's ability to recover. Prior estimates were prepared on a different basis and are not comparable.