Train services have been ramped up as schools reopen and workers are encouraged to return to offices.
Industry body the Rail Delivery Group (RDG) said timetables will be increased to around 90pc of pre-coronavirus pandemic levels.
This will mean additional and longer trains on many routes, particularly at peak times.
From Monday, Greater Anglia said over 93pc of its services will be running, with over 95pc of normal rush hour seating capacity provided, as a result of longer trains being in place on some services.
MORE: Child only buses to be introduced to help public transport cope with schools reopeningMost routes have a full service in operation, with only some Norwich-London Liverpool Street intercity and Stansted Express services yet to be reinstated following the easing of lockdown.
Anthony Smith, chief executive of passenger watchdog Transport Focus, said existing and returning passengers will welcome the capacity increase as “many will now have more choice and a better chance of maintaining social distancing”.
He went on: “The rail industry must focus on maintaining good performance so that passengers can travel with confidence. Disruption and any crowding from this will be especially unwelcome and has the potential to damage trust in the railway.
“The industry also needs to keep an eye on passenger numbers, and check if gaps in services are causing problems.”
Greater Anglia has put in place extensive additional cleaning measures across its network. The company is using powerful cleaning equipment to attack germs on trains and stations in a bid to keep people safe from Covid-19.
With thousands of pupils returning to schools and colleges, extra people are being deployed to help at stations used by young people travelling to school or college, to help them travel safely, by observing social distancing and wearing face coverings.
Greater Anglia has written to schools with large numbers of students travelling by rail to let them know what safety precautions have been taken to protect their pupils and a blog has been produced for students to help them travel with confidence.
Martin Moran, commercial, customer service and train presentation director, said: “We’ve been working hard to make sure people can return to work, school or college, confident that they will be safe on our trains.
“We’ve been running the railway throughout the pandemic and we’re very much looking forward to welcoming our customers back.”
MORE: ‘This will cause huge problems’ - Parents facing school bus seats uncertaintyLatest figures from the Department for Transport show rail usage in Britain is still only at 31pc of pre-pandemic levels.
Timetables were slashed in March as the virus led to a reduction in available railway workers and demand for travel.
But services were increased to around 80pc of normal levels following uplifts in May and July.
Some operators are returning to normal refund rules on Monday after restrictions were eased due to the pandemic.
This means season ticket refunds will no longer be backdated up to 56 days from the last date of travel, and admin fees of up to £10 may return for refunds of single or return tickets.
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules here