Playing in Japan with Toyota Verblitz, the 32-year-old will return home next year to be available for selection and will be back playing for the Auckland-based Blues in Super Rugby in 2025, New Zealand Rugby (NZR) said in a statement on Monday.
"It's a huge privilege to put on the black jersey and one I will never take for granted," the All Blacks full-back said.
Barrett, along with his younger brothers Scott and Jordie, was in the starting 15 of the All Blacks' 12-11 defeat by South Africa in this year's World Cup final in France.
The 123-test All Black has been a key part of their success since his 2012 debut, scoring 734 points and 43 tries across a career that included the 2015 World Cup triumph in England.
Barrett's signature is a coup for Robertson as the former Crusaders' boss looks to regenerate an All Blacks squad that have lost plenty of experience and a slew of great players to retirement since France.
"Beauden brings an enormous amount of class to the table," Robertson said in the NZR statement.
"He is the second most-capped All Black back in history for a reason and to have his knowledge and experience in our game is a reflection of his loyalty."
