Bus Eireann has advised customers to travel "as early as possible" if they're attempting to head home for the Christmas period.
The transport giant says final departures before Christmas will leave at 9pm on Christmas Eve, with services not resuming until St Stephen's Day.
And customers are being urged to reserve their seats on routes where that's possible, ahead of a festive season that's likely to see thousands travelling between counties.
Intercounty travel restrictions will ease from midnight tonight, meaning people can move around the country until January 6.
Bus Eireann will run on a Sunday schedule on December 27 and 28, with normal 'weekday' services starting again on December 29.
Allen Parker, the chief customer officer with the bus service, said: "Demand is somewhat unpredictable this year and all our services are restricted to 50% capacity.
"We encourage people to plan their travel, to consider travelling as early as possible and at off-peak times, and to use seat reservation where that is available.
"We would like to thank customers for their cooperation and understanding, and our staff for all their efforts as they work throughout the holiday period.
"It has been a very challenging year, we want everyone to travel safely and look forward to a healthy and safe 2021."
While travel is allowed over Christmas, Micheal Martin has warned in recent days that restrictions could be reintroduced earlier than the scheduled January 6 date.
The Taoiseach said that special Cabinet meeting has been scheduled for Tuesday, December 29, to reassess the situation.
A worsening Covid-19 picture across Europe has led the Taoiseach to say he's "keeping an eye" on the date.
Intercounty travel reopens this Friday and there are fears that it could lead to a huge spike in Covid cases - especially when the numbers of loved ones travelling home from regions abroad where rates are skyrocketing again is factored in.
This was supposed to last through to January 6.
But it now appears that an earlier return to a higher level of lockdown could be on the cards.
