We've had to cut our prices due to cost of diesel
Trading conditions continue to be tough due to high fuel prices, said the owner of one small firm.
Debbie Stewart from the United Bus Company, based in Carrickfergus, employs three people and runs three vehicles across the greater Belfast area.
"We started up about a year and a half ago, and because of the recession we are already having to charge less for all our jobs," she said. "It is tough enough out there and it means things like advertising and promotion have to take a back seat."
One business body said the OFT fuel prices report is bad news for millions of firms like Debbie's.
Wilfred Mitchell, policy chairman at the Federation of Small Businesses (below) said that there has been a "remorseless" increase in the price of fuel at the pumps.
"We believe there is a clear disconnect between wholesale fuel prices and the price hard-pressed motorists are forced to pay at the pump," he said.
"When the price of oil increases fuel price rises follow soon afterwards, but reductions in the wholesale price are not being passed on when it falls.
"Our own research shows too many small firms are having to pass on the rising costs to customers and more than three quarters of members believe their business is being negatively impacted by the high cost of fuel.
"The FSB is therefore deeply disappointed at the OFT's decision not to launch a full investigation into the workings of the UK road fuel market.
"We believe that tough action is needed against those profiting at the expense of road-dependent small businesses.
"We do welcome the OFT's decision to highlight the difficulty consumers have in accessing fair fuel prices on motorways as well as the uncompetitive practices of some supermarket fuel retailers.
"We still maintain the simplest way to address the high cost of fuel is to lower the amount of fuel tax UK consumers pay, one of the EU's highest. This is what we want to see addressed at the Budget this year."
Both the RAC and AA also criticised the findings.