Private data-center construction in the US ran at a seasonally adjusted annual rate of $96.5 billion in September 2026, the highest in the series, which starts in January 2014, according to the US Census Bureau’s construction spending release of 2 November. Total US construction spending fell 1.9% in the same month.
Data centers made up 4.4% of all US construction spending in September, up from 2.0% in January 2025, by our arithmetic from the Census tables.
Animated chart. Chart: FourWeekMBA.
The key insight: Private US data-center construction ran at a record $96.5 billion annual rate in September 2026, up 90.3% from a year earlier and 4.4% of all US construction spending, by our arithmetic from Census tables, while total construction spending fell 1.9%, the Census Bureau says.
The September figure of $96,462 million is preliminary. August was revised to $88,815 million and July to $80,718 million, according to the Census private construction time series. A year earlier, in September 2025, the rate was $50,700 million, so September 2026 is up 90.3% year on year, by our arithmetic.
The rate has risen in every month of 2026 so far, according to the series. Month on month it rose 10.7% in June, 11.0% in July, 10.0% in August and 8.6% in September, by our arithmetic.
The third-quarter average, $88.7 billion, was 32.8% above the second-quarter average of $66.7 billion. Annualised, that is a growth rate of about 211%, by our arithmetic, in line with the figure circulating on X.
Private US data-center construction at a seasonally adjusted annual rate, January 2024 to September 2026 (September preliminary), from the US Census Bureau C30 tables released 2 November 2026. Shares of all US construction (2.0% in January 2025, 4.4% in September 2026) are our arithmetic.
What Was Posted on X
US DATA CENTER CONSTRUCTION SURGES AT RECORD PACE DESPITE SPENDING SLUMP
US construction spending fell 1.9% in September, but underlying momentum remains strong, supported by AI infrastructure investment.
Data center construction surged at a record 211% quarterly annualized pace, with monthly growth of 8โ10% over the past four months.
Private nonresidential construction rose 1.1%, its fourth consecutive monthly gain, while residential spending dropped 5.5%.
Data centers now account for 4.3% of total construction spending, up from 2% in early 2025.
Walter Bloomberg (@DeItaone) flagged the September Census data on X, citing a 211% annualised quarterly pace for data-center construction. We recomputed it from the Census tables: the third-quarter average was 32.8% above the second quarter’s, about 211% annualised, and the data-center share of all construction was 4.4% in September (the post says 4.3%).
The Rest of US Construction Went the Other Way
Total construction spending was $2,186.1 billion in September, 1.9% below August’s revised $2,227.4 billion, the Census release says. Private construction fell 2.4% to $1,639.3 billion: residential fell 5.5% to $848.8 billion, while private nonresidential rose 1.1% to $790.6 billion. Public construction was $546.8 billion.
Excluding data centers, private construction fell 3.1% from August, by our arithmetic. Data centers added $7.6 billion to the annual rate in the month while the rest of private construction lost $48.6 billion.
A Correction to Our August Read
Census counts data centers inside its office category. In September they were 66.2% of private office construction, by our arithmetic, up from 48.6% a year earlier. Office construction excluding data centers was $49.2 billion, down 8.4% from September 2025.
This morning we reported, from the preliminary August figures, that data centers were 63% of US private office construction at an $85.0 billion rate. With August revised to $88.8 billion, the August share is 64.3%, by our arithmetic.
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As we read the Census tables, data centers are now large enough to move the US construction totals on their own: in September they added $7.6 billion to the annual rate while the rest of private construction lost $48.6 billion, by our arithmetic.
As we read it, the office category is now mostly data centers: excluding them, office construction was $49.2 billion in September, 8.4% lower than a year earlier, by our arithmetic, so the headline office number reflects data-center work more than offices.
US Census Bureau, September 2026 construction spending release
“Construction spending during September 2026 was estimated at a seasonally adjusted annual rate of $2,186.1 billion”
Three Implications
FOR THE CONSTRUCTION DATA Data centers were 4.4% of all US construction spending in September versus 2.0% in January 2025, and 66.2% of private office construction, by our arithmetic from the Census tables.
FOR REVISIONS Census revised August from the $85.0 billion preliminary figure we reported this morning to $88.8 billion; September is preliminary and will be revised too.
FOR THE WIDER ECONOMY Total construction fell 1.9% and residential 5.5% in September, the Census release says, while data-center construction rose 8.6% from August, by our arithmetic.
What Is Not Established
The September number is preliminary and Census revises it; August moved from $85.0 billion to $88.8 billion in one month. The series measures the value of work put in place each month at an annual rate, not new projects announced or the full cost of a finished campus, and it does not include the chips and servers inside. Census does not break data-center spending down by company or state in these tables.
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Census data published on 2 November put private US data-center construction at a record $96.5 billion annual rate in September 2026, up 90.3% from a year earlier and 4.4% of all US construction, by our arithmetic, in a month when total construction spending fell 1.9%.
A note on sourcing. Levels are from the US Census Bureau’s September 2026 construction spending release (2 November 2026) and its C30 seasonally adjusted time-series tables; September is preliminary and July and August are revised. Growth rates, the annualised quarterly rate, shares and ex-data-center figures are our arithmetic from those tables.
Gennaro Cuofano is a CRO and tech executive who has worked in AI since late 2015, starting with bringing NLP, natural-language generation, voice and chatbot products to the marketing industry. His background is in law and finance: he holds a Master's degree in Law and an International MBA with an emphasis on corporate finance (LUISS Business School and the University of San Diego, 2012), and worked as a financial analyst at a real-estate investment firm in San Diego and as an assistant controller. His work focuses on business model strategy, business engineering and, more broadly, structural analysis: how companies make money, read from their own filings. He created FourWeekMBA and leads research there and at The Business Engineer, his newsletter on AI and business strategy, with over 95,000 subscribers and more than 1,000 published analyses. His writing has also appeared on Entrepreneur (for example, How to Digitize a Family Business in Europe) and HackerNoon. Find him on LinkedIn and Substack. See how we source.
