People commuting from Sallins can expect an increase in fares, while those travelling from Newbridge or Kildare Town will see a decrease.
Commuters in Kildare are set to see their train fares rise or fall depending on where they live.
From Monday, a new Dublin commuter zone will be in operation, meaning anyone within a 50 kilometre radius of the capital will be able to use their leap card.
People commuting from Sallins can expect an increase in fares, while those travelling from Newbridge or Kildare Town will see a decrease.
The changes will see a rebalancing of fares within the zone, which covers train stations from Drogheda to as far south as Rathdrum.
Mark Gleeson from Rail Users Ireland says it's a major shake-up of the system, with people commuting from Sallins "not feeling too good" about the changes on Monday morning.
They will be moved from the Short Hop Zone to Zone 2 which, compared to last year, means they will be "worse off", Gleeson said.

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