As of December 2025 Arthur J. Gallagher & Co. has a market cap of โฌ54.07 Billion. This makes Arthur J. Gallagher & Co. the world's 353th most valuable company by market cap according to our data. The market capitalization, commonly called market cap, is the total market value of a publicly traded company's outstanding shares and is commonly used to measure how much a company is worth.
On Dec 4th, 2025 the market cap of Arthur J. Gallagher & Co. was reported to be: