Flanker Hamish Watson has extended his contract with Edinburgh by two years while lock Ben Toolis has signed a new one-year deal, both starting from June.
Watson, 23, joined Edinburgh in 2011 as an academy player before becoming a full-time professional and has made 24 appearances for the capital club.
Twenty-two-year-old Toolis has been at Edinburgh since 2013, at first as an academy player and then as a pro.
The 6ft 7in former volleyball international has made 14 appearances.
Born in Brisbane, Toolis qualifies to represent Scotland through his Lanarkshire-born mum, Linda.
He said: "Obviously things have happened a bit sooner than I expected and I'm really happy, it's the right decision for me. Now I'm getting game time, Edinburgh are on the rise and I want to be part of it.
"Getting the full 80 minutes in both games against Glasgow to win the 1872 Cup, sharing that experience with the boys, was really special. Last Friday's match was definitely the biggest game of my career so far."
"I want to keep getting good game time, keep playing well for Edinburgh and helping to back up our performances."
Scotland Under-20 cap Watson was invited to train with the full Scotland squad ahead of the autumn Tests in November, but broke his jaw in Edinburgh's European Cup win over Lyon.
He returned to the fray with a substitute's appearance in on 2 January.
"It's great to know, so early, that I'll be with the club for the next two seasons," he said.
"Last season my opportunities were a bit limited, then I started the first game after the summer and got into a good run.
"The highlights for me this season have been that first game beating Munster away, the win in France over Bordeaux-Bègles and the last five minutes when I came off the bench in the 1872 Cup win last Friday.
"That gives us great momentum going to Connacht this weekend and, as a team, we want to push into that top six in the league.
"These are really exciting times, going forward."
Meanwhile, Edinburgh have announced that winger Nikki Walker has left the club "to concentrate on his coaching duties with Hawick RFC".
The 24-times capped Scotland international made two appearances for Edinburgh since joining from Worcester Warriors last season.