Many from Ontario heading over the U.S to work and just figure "I'm royalty, I can do whatever I want". Canadians, not Mexicans, represent largest number of visa overstays in the U.S., according to Department of Homeland Security OTTAWA — U.S. President Donald Trump may want to build a wall along the Mexican border, but, in recent years, studies suggest the majority of unauthorized immigrants settling in the U.S. have arrived legally — not by crossing the border unlawfully. And according to a new U.S. government report, the largest group of people who enter the U.S. legally and then overstay their welcome aren’t coming across the southern border at all. They’re coming from Canada. Nearly 93,000 Canadians stayed in the U.S. longer than they were permitted in 2017, according to data released Tuesday by the Department of Homeland Security, far more than from any other country. In comparison, Mexico accounted for about 47,000 visa overstays. The new data, which shows that more than 600,000 travellers overstayed their U.S. visas last year, comes as the U.S. government looks to close gaps that have made it difficult to track visitors and ensure they leave when they’re supposed to. Research suggests visa overstays are now a larger source of unauthorized immigrants to the U.S. than undocumented border crossings. The Center for Migration Studies found in a 2017 report that overstays had exceeded illegal crossings every year from 2007 to 2014.