McLaren announced during the 2017 Singapore Grand Prix weekend that they would split from engine supplier Honda at the end of the 2017 season and had agreed on a three-year customer deal to be supplied with Mecachrome-assembled Renault engines. Team boss Éric Boullier described their performance between 2015 and 2017 as a "proper disaster" for the team's credibility. was the first season in McLaren's history when their cars were powered by Renault engines. McLaren also announced that Fernando Alonso and Stoffel Vandoorne would remain with the team for the 2018 season. On 6 November 2017, the team announced that Lando Norris would be the team's test and reserve driver.
