Rome's public transport system will follow a reduced schedule during the main holidays over the Christmas season.

24 Dec. Christmas Eve. All metro, buses, trams and regional train services and Roma TPL buses run until 21.00. Night buses run as normal from midnight.
25 Dec. Christmas Day. ATAC buses, metro, trams and Roma TPL run from 08.30-13.00 and 16.30-21.00.
26 Dec. St Stephen's Day. Service runs according to normal Sunday/festivo timetable.
31 Dec. New Year's Eve. All metro services run until 03.30 at night (early hours of 1 Jan), substituted from 03.30 until 08.00 with nightbuses.
1 Jan. New Year's Day. Entire ATAC and Roma TPL network resumes at 08.00 and follows normal festivo timetable.
For full details see ATAC Facebook page.