The hotel group saw revenues fall from $4.6bn (£3.2bn) to $2.4bn (1.7bn) over the period as the pandemic impacted the hospitality industry.
IGH owns brands such as Holiday Inn, Six Senses Hotels Resorts Spas, Regent Hotels & Resorts, InterContinental Hotels & Resorts, Kimpton Hotels & Restaurants, Hotel Indigo and Crowne Plaza Hotels & Resorts.
Keith Barr, chief executive officer of IHG, said: “2020 was clearly the most challenging year in our history, with Covid-19 heavily impacting demand across our industry.
“2021 has begun with many of these challenges still in place, with more meaningful progress towards recovery for the industry unlikely until later in the year and dependent on global vaccine rollouts, lifting of restrictions and an acceleration in economic activity.”
He added: “The shape of recovery remains varied globally, but we’ve continued to outperform the industry in key markets thanks to the strength of our teams, business model and segments in which we compete.
“This includes our industry-leading position in upper midscale, where demand remains stronger.”