The Massachusetts fishing magnate known as "The Codfather" is scheduled to plead guilty to federal charges of evading fishing quotas and smuggling money to Portugal.
The US attorney's office says Carlos Rafael has a change of plea hearing scheduled for Thursday.
Rafael is the owner of one of the nation's largest commercial fishing operations, with more than 30 vessels in his fleet, 44 commercial fishing permits and the Carlos Seafood business in New Bedford.
Federal authorities say he falsely claimed his vessels caught haddock or pollock, when they had actually caught other species subject to stricter quotas. He then sold the fish for cash, some of which was smuggled overseas.
He was indicted on 27 counts last May and is free on $2 million (NZ$2.9m) bond.