After a run of four league matches against Getafe without being directly involved in a goal, Benzema headed Madrid in front an hour into Tuesday's clash.
In a match of few clear-cut opportunities, Benzema had previously gone close to breaking the deadlock when he hit the bar 14 minutes in.
Ferland Mendy made sure of what could prove a valuable victory, given city rivals and LaLiga leaders Atleti were pegged back late on and could only draw with Celta Vigo on Monday.
Madrid relied on Raphael Varane to snatch a late winner at Huesca last time out but aimed to make a fast start this time around – Casemiro blazing over from point-blank range before Benzema's header struck the crossbar.
Los Blancos saw just under 70 per cent possession in the first half, yet ultimately their only shot on target came when Luka Modric forced David Soria into an awkward stop.
Soria was called into action much sooner in the second half, making himself big to deny Benzema from a tight angle.
A neat passage of play from Getafe saw Marc Cucurella get into a similar position down the other end, yet the former Barcelona man's touch let him down.
Getafe were duly punished – Benzema making no mistake on this occasion as he directed Vinicius Junior's pinpoint cross beyond Soria.
It was 2-0 six minutes later, Marcelo drilling a low left-wing cross to the front post, with Mendy on hand to turn home his first LaLiga goal of 2020-21.
Benzema curled wide soon after, but Getafe never came close to testing Thibaut Courtois as Madrid cruised to a routine triumph.