The streak, led by two-time MVP Alexander Ovechkin, the league's second-leading scorer with 76 points, 35 goals, 41 assists, started Jan. 13 with a 5-4 shootout victory at Florida.
It was Washington's longest winning streak since Jan. 27-Feb. 18, 1984, and included nine straight victories on home ice.
The run continued despite the absence of star defenseman Mike Green, who received a three-game suspension without pay for elbowing Florida's Michael Frolik Friday during a 4-1 win over the Panthers.
"My emotions are mellow," Boudreau said following Sunday's 3-2 decision against the Tampa Bay Lightning.
"The success we've had doesn't make us feel like fat cats," right wing Mike Knuble told NBC4 television. "We work hard (but) have a long way to go (before the post-season)."