Motorists could save thousands of euro a year by switching to public transport, it has been claimed.
Bus Eireann said rising fuel prices meant it was cheaper to use city bus services for a month than fill up a tank of petrol.
A survey carried out by the company also found the annual cost of fuel for travelling by car between Kells and Dublin is around 4,725 euro.
"However, if that person was to take the bus between Kells and Dublin using a Bus Eireann weekly ticket, it would cost them 2,702 euro a year - a saving of over 2,000 euro," said a spokesman.
Bus Eireann said those eligible for tax-saving schemes could avail of even further savings.
In a separate example, it compared the 14.50 euro cost of a return bus ticket between Galway and Ballinasloe with an estimated petrol bill of more than 20 euro for the same trip by car.
"With petrol and diesel prices increasing it is getting more and more expensive to use the car," a spokesman said.
"Commuters who leave the car at home a couple of days a week and take the bus instead could cut their bills by hundreds of euro a year."