Those wishing to travel home for Christmas on the country's rail and road services today are being advised that services will be busy throughout the day.
An estimated 400,000 people are expected to travel on Iarnrod Éireann trains between now and New Year's Day, including thousands of commuters today.
Iarnród Éireann will have a full schedule until 6pm this evening, when services will be reduced.
There will be no intercity trains on Christmas Day or St Stephen’s Day. Normal services are due to resume after this point.
DART and commuter lines are also due to operate on a reduced service from this evening.
Barry Kenny of Iarnród Éireann has appealed to passengers to use the luggage storage available on trains.
"There’s a lot of luggage storage, and we would appeal to people: use the storage areas, don’t put luggage in bike areas and particularly don’t put luggage in wheelchair areas," he told RTÉ’s Morning Ireland.
Around 700,000 people are expected to use Bus Éireann services over the coming week.
There will be no services on Christmas Day, but there will be a full Sunday service from St Stephen’s Day with normal services resuming on 27 December.
John Sheridan of Bus Éireann has said that it will be operating a normal schedule up until around 9pm this evening.
"There’s no service tomorrow Christmas Day. However, from the following day [St Stephen’s Day], we’re back operating a Sunday schedule, and then from the 27th we’re back operating normal services right throughout the Christmas period," he told RTÉ’s Morning Ireland.
"The only exception to that is on New Year’s Eve, where services will start to wind down at 10pm.
"Over the Christmas period, we will experience in or around 700,000 customer journeys. So extremely busy but a full schedule in operation to cater for it."