BUS and rail fares will rise by as much as 18pc within weeks, with passengers who pay by cash the worst-hit.
The National Transport Authority (NTA) has approved fare increases for the second time this year, which will affect commuters living in Dublin the hardest.
In some cases, the NTA approved hikes above those sought by the public transport companies.
The authority defended the move, saying it would protect services and encourage people to switch to pre-paid tickets.
The highest increases will be for short bus journeys in Dublin paid for in cash. Fares will rise by up to 17.9pc, with longer journeys of more than three stages going up by 6pc. Multi-travel tickets such as the 10-journey Travel 90 card will also go up by nearly 17pc.
Fares on national Bus Eireann routes will increase by an average of 6pc, while Irish Rail prices will rise by an average of 10pc for DART and commuter services and 3pc for inter-city. Luas tickets will increase by up to 6pc.
The price hikes are expected to yield €22.3m for Dublin Bus, Bus Eireann, Iarnrod Eireann and the Railway Procurement Agency (RPA), which operates the Luas.
They were sharply criticised by passengers' lobby group Rail Users Ireland. "We're very concerned about increases," said spokesman Mark Gleeson.
"It is ridiculous that the NTA approved fares above what the companies sought. To see a 10pc hike on commuter fares, on the least loss-making part of the network, is shocking. The huge concern is they were given more than what they asked for."
But the NTA said the increases were needed to protect services, and that discounts averaging 10pc were available by using pre-paid or Leap cards.
"People will still be able to get a lot of value from the pre-paid products and the leap fares," said public transport services director Anne Graham.
The increases come after it emerged that the CIE group of firms lost €40m last year, with the RPA recording a €4m loss.
CIE admitted that bus and rail passengers would be hit with years of repeated fare hikes as the cash crisis deepens. Its auditors have issued warnings over whether it could continue as a going concern.
CIE passenger numbers peaked in 2007 when 288.7 million journeys were made on public transport. But this fell to 232.7 million last year. Mounting fuel bills, falling passenger numbers and cuts in state aid have worsened the crisis.
The fare hikes drew calls for an overhaul at CIE from Fianna Fail's transport spokesman Timmy Dooley. "The package that CIE offers at the moment is not attractive to customers and this needs to change," he said.
The price hikes come into effect from December 1 at the earliest. Luas said they would not take effect until January.