Translink said the changes are in response to fewer people using its services following the NI Executive regulations and guidance on essential travel.
It explained the timetable revision will allow contingency plans to be put into place for increasing levels of Covid absence which will give passengers “a level of certainty to plan their bus and rail services with confidence”.
Ian Campbell, Translink director of service operations said; “The revised timetables allow us to maintain service levels, prioritising school and peak time services and ensuring overall geographic coverage of the network is retained to enable people to continue to travel safely.
“We continue to make our network and services safe with the use of extensive cleaning and sanitising of our vehicles and stations using anti-viral products; putting a wide range of customer communications in place; as well as ensuring our services are well ventilated.
“We would remind everyone that you must, by law, wear a face covering on public transport.
“The NI Executive recently announced changes to the regulations regarding exemptions and it will be important for everyone to familiarise themselves with changes to the legislation.
“We also encourage everyone to practice good hand hygiene, keep windows open where possible on board, socially distance when possible and use contactless payments to minimise interaction, so together, we can keep everyone safe and limit the spread of the virus.
“Customers should familiarise themselves with the latest changes to their specific services in case they need to adapt their usual travel plans.
“For the latest timetable updates use the Journey planner or visit the website www.translink.co.uk or call the contact centre on 028 90 66 66 30,” he added.