The global in-home TV audience watching at least one minute of the coverage accounted for almost 3.3 billion viewers, a 2.2 percent increase on the 2014 edition hosted in Brazil, according to FIFA's audit of audience data published on Friday.
A further 309.7 million caught the action on digital platforms, public viewing areas or in bars and restaurants.
France's 4-2 victory in the final, which gave them their second World Cup title following their triumph in 1998, was the most watched game of the competition.
It was followed by England's semi-final defeat to Croatia and the other last-four clash between France and Belgium.
"These figures really do support the claim that Russia 2018 was the best World Cup ever," said FIFA's chief commercial officer, Philippe Le Floc'h.
"The fact that half the world's population watched the FIFA World Cup reflects not just the high quality of our award-winning live coverage, but also that fans everywhere are insatiable for world-class football."
The World Cup coverage reached around 1.6 billion individuals in Asia, with 655.7 million viewers (18.4 percent of the global total) in China, who failed to qualify for the tournament.
The 2022 edition of World Cup will be held in Qatar.
(Reporting by Hardik Vyas in Bengaluru; Editing by Toby Davis)
