About one in three UK companies are unaware that TMCs receive kickbacks from their preferred suppliers, a survey by hotel booking company HRS claimed.
The poll for the UK Companies Business Travel Report said that of those companies which were aware of the commissions, 60% received no rebate for themselves.
The survey questioned 300 companies ranging from 50 FTSE 500 companies to 250 in the SME market.
The report said that the findings revealed that about half the SMEs had "lost faith in the corporate travel industry" and that a quarter of the FTSE 500 companies had "turned their backs on traditional travel management companies."
The HRS report said that 40% of companies paid on average £27 commission for an airline booking, just over 25% paid £18 for a room reservation, 20% paid £20 for a train booking and the same number paid £25 to book a car.
The survey also found that only 5% of companies expected to receive advice on the best prices or deals, just 9% to get advice on visas and other travel documents, only 8% expected advice on vaccinations and 3% guidance on flight changes, delays and security.
Mr Grant Appleton, HRS's UK commercial director, said the aim of the survey was to "find the levels of transparency and integrity in the industry."
He said many companies did not realise that agents were often being paid twice by both the customer in fees and by the hotel in commission.
“We want companies to get better access to better prices for rooms, planes, trains and cars as well as access to a whole world of competitors.
"As far as integrity is concerned, what you see is not necessarily a fair indication of what is available but what the travel agencies wants you to see.
"We want to make businesses aware of the hidden costs and the hidden commissions and that they are not being offered a real choice," he said.
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