The Washington Capitals have filled their biggest need on the NHL's first day of free agency by signing Stanley Cup champion goaltender Darcy Kuemper to a five-year, $26.25million contract.

Kuemper joins the Capitals off a highly successful lone campaign in Colorado in which he tied for fourth in the NHL in wins (37) and shutouts (five) and ranked fifth among qualified goaltenders with a .921 save percentage during the regular season.

The 10-year veteran then posted a 10-4-1 record with a 2.57 goals against average in 16 postseason starts to help the Avalanche to their first championship since 2001.

"Darcy is an established starting netminder who proved that he can win on the game's biggest stage, and we are excited to welcome him to Washington," Capitals senior vice president and general manager Brian MacLellan said Wednesday in a statement.

"We feel this signing will provide our team confidence and stability in net."

Kuemper, an All-Star in 2019-20 with the Arizona Coyotes, will be asked to stabilise a position that was often inconsistent for the Capitals last season.

Washington netminders combined for an .898 save percentage in 2021-22, the lowest of any team who reached the playoffs, and the team have since parted ways with their two main goalies from last season in Vitek Vanecek and Ilya Samsonov.

Vanecek was traded to the New Jersey Devils last week, and Samsonov signed with the Toronto Maple Leafs after the Caps declined to tender a qualifying offer to the restricted free agent.

Washington also signed former St. Louis Blues goaltender Charlie Lindgren to back up Kuemper, who owns a 143-95-36 record with a 2.48 GAA and .918 save percentage in 299 career games with Minnesota, Los Angeles, Arizona and Colorado.

The Avalanche prepared for Kuemper's expected departure by acquiring Alexandar Georgiev from the New York Rangers last week and signing him to a three-year, $10.2m deal. Georgiev will compete with holdover Pavel Francouz for Colorado's number one netminder job.