Trade body the Business Travel Association (BTA) said latest figures from data firm Travelogix show in the second week of August international corporate trips from the UK dropped by 85.3% compared to the same week in 2019.
There were 314,477 fewer international and domestic business trips.
The BTA said travel restrictions to ten key destinations, including Germany and the US, equated to a loss to UK GDP of £3.15 billion last week, plus £942 million from lost business travel within the UK.
Business travel appears to be set for a comeback, however.
A study released last month by travel and expense management services firm, SAP Concur, found 95% of corporate employees surveyed were willing to begin travelling for work again.