He received a qualifying offer for one year of $15.8 million, but declined it. On February 4, 2016, Kendrick re-signed with the Dodgers on a two-year, $20 million contract. Kendrick and his agent blamed the fact that he declined the qualifying offer and thus would require any team claiming him to give up a draft pick with the lack of interest in him from other teams during his free agency. With Chase Utley getting most of the work at second base, Kendrick played primarily in left field but also saw time at third base and first base in addition to second. He appeared in 146 games and hit .255/.326/.366 with eight homers and 40 RBI. For the season, he had the highest ground ball percentage (61.0%), and the lowest fly ball percentage (19.6%), of all major league hitters. Kendrick was traded to the Philadelphia Phillies for Darin Ruf and Darnell Sweeney on November 11, 2016. On April 18, 2017, Kendrick was placed on the 10-day disabled list due to a strained right abdomen. On July 28, 2017, the Phillies traded Kendrick and cash considerations to the Washington Nationals for McKenzie Mills and international signing bonus money. On August 13, Kendrick hit his first grand slam, a walk-off in the bottom of the 11th, against the San Francisco Giants. He batted .293 that season, finishing with 7 HR and 25 RBI. He primarily played left field. He re-signed with the Nationals after the season for two years and $7 million plus incentives. On May 19, 2018, Kendrick ruptured his Achilles, ending his season early. He finished the season batting .303 with 4 HR and 12 RBIs. Kendrick participated in 121 regular season games in 2019, finishing with a batting average of .344 in 330 at bats, alongside 62 RBIs and 17 home runs, second-most of any season in his career. He primarily played first base. On October 9, 2019, in Game 5 of the National League Division Series, Kendrick hit a grand slam in the 10th inning off of Los Angeles Dodgers pitcher Joe Kelly to give the Nationals a 7-3 lead that held up as the final score, advancing the Nationals to the National League Championship Series. It was just the second extra-innings grand slam in MLB postseason history, the other being hit by Nelson Cruz in the 2011 American League Championship Series. In the National League Championship Series, Kendrick went 5 for 15 with 4 doubles and 4 RBIs in the Nationals' four-game sweep of the St. Louis Cardinals, earning him the National League Championship Series MVP award.