In an expansion of the SPFL Cup competition, the two clubs become the first ever English sides to enter the competition, where they will join at the Second Round stage.
Following approval from UEFA, the two highest ranking sides from the 2017/18 Vanarama National League season will compete in the knock-out tournament, comprising of teams from Ireland, Northern Ireland, Wales and, of course, Scotland.
Michael Tattersall, Chief Executive at The National League, said: “We were pleased to accept the SPFL’s invitation to participate in next year’s competition.
“We believe our two clubs will benefit from playing in an international competition and we look forward to establishing new relationships with the other leagues involved.”
Bruce Elliott, Chairman of Sutton United, said: “We're delighted to have been asked to compete in the Irn-Bru Cup.
“Both manager Paul Doswell and I are excited at taking part in a competition that is new for us, and gives us the chance to encounter new opposition and play against sides that we would not meet in our normal schedule. We are thoroughly looking forward to it.”
Manager of Boreham Wood, Luke Garrard, said: “I think that it will give the players an added incentive and I am extremely excited that we have the luxury of possibly travelling around the British Isles for a fixture, I think that it is a huge achievement.
The Scottish Challenge Cup was established in 1990/91 to mark the Scottish Football League centenary and has run every year since (with the exception of 1998/99).
Scottish Championship side Inverness Caledonian Thistle are the current cup holders, beating Dumbarton in this year’s final at McDiarmid Park.