AI infrastructure spending is driving a sharp increase in US bank lending: Commercial and Industrial (C&I) loans at large US banks surged +11.4% YoY in October, to $1.6 trillion, the most since June 2020. This also marked their largest YoY growth since February 2023. In Q3, C&I loans at the 25 largest US banks grew almost +10.0% YoY, the strongest growth in 10 years excluding pandemic-related swings. This represents a sharp reversal from an -8.0% YoY contraction in Q4 2025. The surge has been driven by rising borrowing demand from Big Tech companies and data-center developers to fund AI infrastructure projects. At the same time, regional lenders are providing credit to construction companies and other businesses benefiting from the investment boom. The data-center buildout is increasingly being funded by debt.