The bid was announced at a press conference in New York attended by the head of CONCACAF, Victor Montagliani, along with US Soccer Federation chief Sunil Gulati and Mexico counterpart Decio de Maria.
Announcing the bid, US chief Gulati said three quarters of the tournament's matches would be staged in the United States, with Canada and Mexico hosting 10 games each.
Gulati also played down the possibility that the politics of US President Donald Trump could hamper the bid.
"We have the full support of the US government in this project," Gulati said.
"The president of the US is fully supportive... We are not at all concerned at some of the concerns that some people may raise," he added.
Trump was elected last year after a campaign marked by rhetoric against Mexico, vowing to build a wall along the country's southern border to keep out illegal immigrants.
The joint bid will start as the heavy early favourite in the race, despite United States prosecutors leading the investigation into football corruption which rocked the sport in 2015 and led to the downfall of former FIFA supremo Sepp Blatter.
Monday's announcement confirmed what has long been regarded as an open secret amongst FIFA-watchers: that a bid from the North America region for 2026 was inevitable.
That sense of certainty hardened last year, when FIFA's council ruled that neither Europe nor Asia would be eligible to run for the 2026 tournament on the grounds that the regions are hosting the next two World Cups. Russia is hosting the 2018 finals, followed by Qatar in 2022.
With Europe and Asia ineligible, CONCACAF could in theory face potential competition from the Africa, South America and Oceania regional confederations.
US soccer officials had been publicly coy about the possibility of a future World Cup bid since the country lost out to Qatar in the battle for the 2022 tournament at a corruption-tarnished vote in Zurich in 2010.
However the prospect of a fresh American bid gathered momentum in 2014 after the World Cup in Brazil.
That campaign captured the imagination of US sports fans, with huge crowds attending public screenings of games at cities across the country.
The country's club game is also booming, with record average crowds of 21,692 attending Major League Soccer games in 2016.
The United States also burnished its credentials as a major tournament host with last year's 16-team Copa America Centenario, which culminated in Chile's victory over Argentina in front of 82,026 fans at the final in New York.
The United States first hosted the World Cup in 1994, staging a commercially successful 24-team tournament that played out to packed stadia.
The 1994 tournament remains the most attended World Cup in history, with just over 3.5 million fans flocking to its 52 games, an average of 68,991 per match.
Mexico has hosted the World Cup twice before – the 1970 finals won by a Pele-inspired Brazil and the 1986 tournament won by an Argentina team led by Diego Maradona.
Canada, who have only made one World Cup appearance when they were eliminated in the first round of the 1986 finals, has never hosted the tournament.
However Canada earned plaudits for its staging of the Womens' World Cup in 2015, which was won by the United States in the final in Vancouver.
A tournament in North America is also likely to be attractive to FIFA for solid public relations reasons.
With dozens of modern, tournament-ready venues to choose from across the region, there is little risk of stadiums being left to rot as white elephants following the tournament, a problem which has embroiled grounds used at the 2010 and 2014 World Cups.