The 6ft 6in Queensland Reds lock, who weighs in at 116kgs and can also line up in the back row, has 30 Test caps to his name for the Wallabies.
He will arrive at cinch Stadium at Franklin’s Gardens following the conclusion of the 2022 Super Rugby campaign.
After representing Sydney’s Western Suburbs rugby league side at age-group level, Salakaia-Loto came through the Colts and Shute Shield teams for Randwick, also getting selected for Australia in the 2015 and 2016 World Rugby Under-20s Championships.
He signed his first professional contract with Queensland Reds in 2015 and has since enjoyed a stellar seven-year Super Rugby career, making 64 appearances in the competition to date.
His form for the Reds was rewarded with a Test debut for Australia against South Africa in 2017.
Salakaia-Loto then notched up five appearances at the 2019 Rugby World Cup and has also taken his Rugby Championship tally to 12.
But the 25-year-old is now relishing the prospect of proving his ability in the Gallagher Premiership.
“I am incredibly excited to be signing for Northampton Saints, a prestigious club which is known around the world and boasts a long history of success,” Salakaia-Loto said.
“I’ve heard that Franklin’s Gardens is an amazing place to play rugby, and for a long time now, I have wanted to test myself in the Northern Hemisphere.
“The Northampton squad is already filled with talent and I’m just looking forward to getting over to England later this year to try to develop my game, and help the team win some trophies.
“This is a fantastic opportunity for me and my family, so I can’t wait to pull on a black, green and gold jersey for the first time.”