The US trade show had been due to take place over 30 May to 3 June.
Organisers said global travel restrictions, flight reductions, social distancing and worldwide "stay at home" orders had made it "impossible" for this year’s event to go ahead.
Delegates will be updated on the process for credits and refunds next week.
Roger Dow, president and chief executive of the US Travel Association, said IPW would return in 2021, and would be vital to the recovery of US tourism.
“When this health crisis is behind us, IPW will clearly be more vital than ever as a catalyst for activating inbound travel and re-growing commerce, exports and jobs," said Dow.
