SpaceX's $41.1bn compute book rests on four counterparties

SpaceX has signed a fourth major AI capacity contract this year, a hosting deal for an unnamed customer worth $13.3bn a year, lifting total income from data center compute leases to $41.1bn. Chief financial officer Bret Johnson put the figure on the record at the Goldman Sachs Communacopia + Technology Conference 2026, and Investing.com's account of the appearance supplies the monthly arithmetic, $1.11bn, along with the detail that the new contract begins generating revenue in December 2026.

The figure reconciles to names almost to the dollar: SpaceX's three earlier AI agreements this year annualize to $15bn for Anthropic at $1.25bn a month, $11.04bn for Google Cloud at $920m a month and $1.8bn for Reflection AI at $150m a month; add the new $13.3bn contract and the four sum to $41.14bn, within rounding of Johnson's number. The entire book is four counterparties, three of them named in public and one of them not.

The compute business is new and began pointing inward: xAI, SpaceX's subsidiary, was built around Grok, its own large language model, and ran the capacity at the Colossus data center in Memphis for that model's account alone. After the Anthropic agreement, Musk said the company was actively seeking more compute customers, and the Reflection, Google Cloud and unnamed contracts suggest the pivot is working.

Two names carry most of the weight: Anthropic and Google Cloud account for $26.04bn of the annualized total, about 63% of the book, and Anthropic—the larger at $1.25bn a month—is building a data center arm of its own, which, as this publication reported in September, hired the architect of Equinix's hyperscale joint ventures and put the anchor tenant on the cap table. The largest name in SpaceX's booked revenue is simultaneously becoming a developer of the capacity it rents, an unusual position for a landlord.

The concentration is a pricing problem, not a credit problem: Anthropic and Google Cloud are among the best-capitalized counterparties in AI and the contracts are producing revenue rather than paper. A book whose two biggest tenants have the balance sheet to fund their own capacity is a book whose rents face a real alternative at every extension, and the coverage does not disclose the term or structure of any of these agreements.

The leases are only as durable as the capacity behind them, and the capacity is a power question. SpaceX had an estimated 1.4GW of data center capacity live as of June 30, 2026, and aims to cross 2GW by the end of this year before nearing 10GW by the end of 2027—a sevenfold increase in eighteen months. Connection consent is now the scarce input and compute is a derivative of it, which is why the price of a grid connection has become the number that governs a buildout like this one.

Colossus 1 and 2 sit in Memphis, a third data center is planned for Southaven, and development has begun on a fourth around Memphis, but the coverage does not say where the power for a 10GW portfolio comes from, or on what terms.

The public market has already priced an answer: SpaceX listed in June 2026, climbed close to $3 trillion and then retreated to a $2 trillion market cap—a round trip that is the market learning to price a company whose growth story now runs through compute leases. It invites the comparison to the neocloud listings in front of public investors, the ones asking investors to pay infrastructure prices for a $51bn contracted backlog. SpaceX's book is the smaller number, its counterparties are better known, and one named tenant still prices the rest of the digital stack; SpaceX has three of them on the sheet.

A fourth name may be coming from Washington, where in July SpaceX was reportedly in talks with the Department of Defense about a compute contract for the Pentagon that could be worth billions—the same pipeline followed from the federal credit side, where the reported $5bn Fluidstack loan would direct government money at AI's unguaranteed layer. A DoD contract would be the rare counterparty the market can name, rate and read in a filing.

The $13.3bn contract turns on in December, and the $41.1bn stops being a signing total and starts being a run-rate. What the equity has bought, at $2 trillion, is a wager that four customers—three of them known, one of them not—keep paying for capacity SpaceX has not finished building.