Microsoft’s $25 billion bond plan tests how far AAA credit can fund AI

Microsoft plans to raise $25 billion in bonds to support its AI infrastructure expansion, CNBC reported on Thursday. The offerings should close on Nov. 4, according to the company’s statement as quoted by CNBC.

We could not find Microsoft’s own press release or an SEC filing for the sale, so the details below rest on CNBC’s public reporting and on headlines from other outlets. Treat them as reported, not confirmed by us.

What the offering is meant to pay for

CNBC says Microsoft will use the net proceeds for general corporate purposes. Its statement lists working capital, capital expenditures, stock repurchases, acquisitions and repayment of existing debt as possibilities. It does not tie the money to any single project.

CNBC adds that management is targeting $170 billion of capital expenditures in 2026, to serve demand from AI labs Anthropic and OpenAI and from other customers. It notes that Microsoft holds a top-tier AAA rating from S&P.

A finance chief who had not yet used the bond market

On Wednesday’s earnings call, finance chief Amy Hood said Microsoft would draw on extra funding sources alongside its own cash flow when conditions are attractive, per CNBC. She said the company had been using leasing as a vehicle. In CNBC’s account of her remarks, she said Microsoft has access to the debt markets because of its ratings and had not yet tapped them. The offering follows that remark by a day.

Positive cash flow sets Microsoft apart from its rivals

The contrast with other large spenders is the core of CNBC’s story. It reports that Microsoft posted positive free cash flow on Wednesday, while Alphabet’s was negative for a second quarter in a row. Meta reported negative free cash flow last week, and Amazon did so on Thursday. CNBC also says Oracle unveiled a plan on Wednesday to raise $10 billion of new debt, and expects positive free cash flow again in the second half of its 2028 fiscal year.

CNBC notes that investors have become more wary of heavily indebted companies as central bankers raise interest rates to fight inflation. Amazon, Alphabet and CoreWeave have all used debt markets to fund infrastructure this year, it adds.

What other reporting adds

Techmeme’s summary of a Bloomberg report, which we have not read in full, describes the sale as Microsoft’s first US investment-grade bond offering since 2017, when it raised $17 billion. If that holds, the company is returning to a market it left for years while its AI spending climbed. Neither report says how the bond proceeds would be allocated.

The move fits a pattern we have followed across the sector, where financing is becoming as important as chips. Our earlier coverage looked at a GPU lease structured as a five-year rent schedule and at Nvidia’s possible debt backing for a site Anthropic plans to use. Microsoft, with an AAA rating, is borrowing in a very different position from those smaller players.

What the reports do not establish

CNBC’s text, as available to us, gives no breakdown of maturities, interest rates or the number of tranches. It also does not say how much of the $170 billion Microsoft expects to cover with debt. Those details would normally appear in the prospectus filed with the offering. Until Microsoft publishes it, the size and timing are the firm facts, and the use of proceeds remains broad by the company’s own wording.