The deal, which is expected to be north of $9 million per season, can’t officially be signed until March 1.
The Golden Knights dealt defensive prospect Erik Brannstrom, forward Oscar Lindberg and a 2020 second-round pick to the Senators in exchange for Stone on Monday, minutes before the 3 p.m. ET trade deadline.
The 26-year-old was widely considered the best player available at the deadline after failing to come to terms on a long-term deal with the rebuilding Senators in the lead-up to the deadline.
Stone is in the midst of a one-year, $7.35-million deal and has 28 goals and 62 points through 59 games so far this season.