Microsoft, Alphabet, Meta and Amazon spent a combined $208.7 billion on capital expenditure in the July to September quarter, according to their third-quarter 2026 reports, in the clearest test yet of whether the AI build-out pays for itself. Amazon led at $77.3 billion, followed by Alphabet at $51.4 billion, Microsoft at $45.2 billion including finance leases, and Meta at $34.9 billion.

The market's verdict was harshest where cash flow no longer covered the bill. Alphabet's free cash flow turned negative at $9.07 billion after $51.4 billion of capital spending outran $42.3 billion of operating cash flow, and its shares fell 12.64% on 29 October. Meta spent $34.9 billion against $32.8 billion of operating cash flow, leaving free cash flow of minus $2.12 billion; its shares fell 6.98% after results and lost 15% in October, its worst month in four years.

Microsoft was the exception. Operating cash flow of $58.0 billion covered $39.4 billion of cash capital spending, leaving $18.6 billion of free cash flow, and its shares closed almost flat. Cloud growth stayed fast: Azure revenue rose 48% to $33.2 billion, Google Cloud jumped 103% to $30.7 billion, and Amazon Web Services grew 39% to $46.0 billion, its fastest since 2021.

The gap is being financed in the capital markets. Microsoft priced $25 billion of bonds on 29 October, Alphabet raised $28.7 billion of notes and sold $12.4 billion of stock, Meta sold $12.5 billion of convertible preferred stock, and Amazon took in $48.1 billion of debt. S&P Global also cut Meta's outlook to negative on 30 October, keeping its AA- rating. With Alphabet guiding to $195-205 billion of spending in 2026 and more in 2027, investors now sort the builders by cash coverage, not cloud growth alone. Averin's full breakdown sets out the figures company by company.