Twenty-four-year-old Savea and 21-year-old Barrett have recommitted through to the end of the 2019 season.
Twenty-five test Savea made his Super Rugby debut for the Hurricanes in 2013 and All Blacks Test debut in 2016, while Barrett made his Super and Test debut in 2017. He has played five Tests.
"Wellington is my home town and it's great I can stay here and contribute as much as I can for the Hurricanes," said Savea.
"Also, we all know how important next year is for the All Blacks with the Rugby World Cup in Japan and I really want to be a part of that campaign."
Barrett said he was enjoying his rugby.
"Hopefully I can play my part in helping the Hurricanes go as far as we can this season and next, and if my form warrants it, I can also be involved in the All Blacks."
All Blacks' coach Steve Hansen added said it was "great" to have both involved.
"Ardie and Jordie are both incredibly talented footballers in their own right, have been outstanding in our environment and done the jersey proud - and we look forward to working with both of them."
John Plumtree, who will take over as Hurricanes' coach in 2019, was delighted to them onboard for another year.
"It goes without saying that they are both world-class players.
"Ardie has become an important leader within the squad, even though he's still quite young, while Jordie has quickly established himself as one of the best and most versatile players in the competition."