Rail companies are adding more than 2,500 daily services to timetables ahead of the next relaxation of lockdown restrictions.
Industry body the Rail Delivery Group (RDG) said this is the largest increase in capacity this year.
The amendment will be implemented on Sunday, in one of two major annual shake-ups of timetables.
Department for Transport data shows rail travel across Britain was at 38% of pre-pandemic levels on May 3, which is the latest date with confirmed figures.
But demand is expected to increase from Monday when coronavirus rules are eased.
In England, the relaxation includes people being able to meet outdoors in groups of up to 30, and indoors in groups of six, or two households.
Indoor venues such as cinemas, museums and theatres are reopening, while pubs and restaurants will be allowed to serve customers indoors.
RDG director of nations and regions Robert Nisbet said: “As many people prepare to make their first journey since the pandemic began, we’re ensuring that they can travel with confidence by increasing space and maintaining enhanced cleaning.
“As part of our safer travel pledge, we’ve made journeys more comfortable and reliable for people when they return and while we are adding thousands more daily services to increase space, social distancing may not always be possible.
“We’re therefore asking people to travel at quieter times where they can and to wear a face covering unless exempt.”
Rail minister Chris Heaton-Harris said: “As passengers return to the railways, adding more than 2,500 daily services will help meet demand and support people in travelling safely.
“Train companies will be focusing on ensuring services are comfortable and reliable, and by providing detailed travel information passengers will be able to plan ahead, avoid busier trains and feel confident on their journey.”
On Friday, Great Western Railway announced it will operate 99% of its timetable from Monday following more than a week of disruption due to cracks on trains.
