The British Telegraph is reporting that Piutau has signed a deal with Championship side Bristol worth nearly $2 million.
The newspaper says Piutau's contract is worth $1.8m a year.
The 16-test All Black will join the English club at the 2018/19 season after signed a two-year deal.
He currently has one year left on his deal with Irish province Ulster.
It puts Piutau in the league of former All Black Dan Carter for pay.