The U.S. owes nearly $1.5 billion for the regular U.N. budget and nearly $1.2 billion for the peacekeeping budget. A country can be up to two years in arrears before facing the possible repercussion of losing its vote in the 193-member General Assembly.
https://www.reuters.com/world/trump-administration-proposes-scrapping-un-peacekeeping-funding-2025-04-15/