As of March 7, the total circulating supply of USDC was US$29.3 billion.

AS the Us USDC 2024-03-09 52
As of March 7th, Circle has issued a substantial amount of 2.6 billion USDC, demonstrating a significant presence in the digital currency market. In the past 7 days alone, they have redeemed 2 billion USDC, further strengthening their position and increasing their circulation by 600 million USDC. This brings the total circulation of USDC to an impressive 29.3 billion US dollars, with an equally substantial reserve of the same amount. Of this reserve, approximately 3.6 billion US dollars are in cash, while the Circle Reserve Fund holds a substantial 25.8 billion US dollars. This indicates a strong financial backing and stability for Circle in the digital currency space.