The report is based on a survey of 2,700 businesses, and suggests that congestion is costing the economy £23.2bn, up £5.7bn a year ago. It is a UK wide survey report by the BBC.
The need for reliable air transport in and out of London's Heathrow was highlighted by businesses across the country rather than just in the southeast.
The report says that "major projects such as a third runway at Heathrow and a new high speed railway must not be put to one side but should be brought forward". It says that two out of five businesses said the busy airport was important to their operation, whereas among larger companies, that rose to three out of five.