The gathering in Liverpool in northwest England "will be the world's largest business showcase," IFB chairman Max Steinberg said today at a presentation in London's Canary Wharf business district.
The conference starts on June 13 and ends on July 1, while Britons on June 23 vote to decide whether or not their country should remain in the European Union.
The campaign has divided the business community, although surveys indicate a majority of British companies would support a "Remain" vote.
"It's a fantastic opportunity for making deals and boosting world business," IFB director Ian McCarthy, who is co-organising the event with Britain's official export promotion agency, told AFP.
Some 300 million pounds in contracts were signed at the first International Festival of Business in 2014, where 3,350 firms took part, and organisers are hoping for more this year.