ScotRail has resumed at least 90% of its services.
The increase on Monday comes ahead of the reopening of schools in Scotland from August 11, with demand for more trains expected.
All routes will have normal early morning, late night, and peak services.
ScotRail said 100% of normal capacity will be provided during peak travel hours, however many seats will need to remain empty to maintain physical distancing.
Commuters are still being urged to consider other travel options including walking and cycling to free up space for those who must use the train.
Face coverings are mandatory at stations and on trains, and anyone who feels ill or has a temperature should not travel.
Due to the suspension of driver training during lockdown, ScotRail said it is not yet possible to return to a full service.
David Simpson, ScotRail operations director, said: “We do need everybody to continue taking personal responsibility for their travel choices because physical distancing can’t be guaranteed.
“Customers who do travel with ScotRail should follow our five rules for safer travel, including the wearing of a face covering on trains and at stations.”
ScotRail’s five rules
- Do not travel if you feel unwell or have a temperature.
- Travel away from the main commuting times (7am-9am and 4pm-6.30pm) wherever possible, as trains will be busiest around then. The earliest and latest trains serve key workers, like NHS and care home staff.
- If you think it’s not safe to board a train, don’t do it and wait for another service.
- Wear a face mask or covering and, where possible, maintain physical distancing.
- Be patient. You might not be able to board your first choice of train, as physical distancing means most seats need to be left empty.