Train operator Northern is reintroducing three-quarters of services which were removed after a timetable change that caused hundreds of delays and cancellations.
The operator slashed nearly 170 services a day - 6% of the total - in early June after a new timetable introduced in May resulted in significant disruption for passengers.
Northern blamed unforeseen delays to electrification projects that resulted in driver training issues, which meant the timetable had to be drawn up and delivered in less than half the usual time.
Mayor of Manchester Andy Burnham has called on the Prime Minister to intervene in "rail chaos" in the north of England that is thought to have cost businesses more than £1 million a day at its height.
The phased reintroduction of services, which will see 75% brought back from Monday and the remaining 25% in September, was recommended by industry bodies.
Northern's managing director David Brown said: "The May timetable caused significant disruption for customers on some routes on our network and we're truly sorry for that.
"We introduced an interim timetable on a number of routes from 4 June, and that has enabled us to accelerate our driver training, stabilise service levels, improve performance and significantly reduce last-minute cancellations."
"Whilst we are ready to reintroduce all 168 daily services, given the need to drive further improvements across Manchester, we have agreed to a more gradual reintroduction of our services. A phased introduction is the right approach to ensure a more stable and reliable service for customers."
The services being reintroduced on Monday are:
- A full service on the Lakes Line of 35 trains a day following a partial reintroduction on July 2
- A full service from Blackpool to Manchester Airport and Manchester Piccadilly of 31 trains in total a day
- A full service from Lancaster to Morecambe with 24 trains a day reinstated
- A full service from Preston and Blackburn with four trains a day reinstated
- 17 daily (of 30 removed) trains between Blackpool South and Colne via Preston
- 10 services a day (of 16 removed) between Ormskirk and Preston
- Four daily (of 10 removed) trains on the Kirkby to Manchester Victoria line via Wigan
The remaining removed services which also include six daily Blackburn to Southport trains and 12 daily Manchester Victoria to Stalybridge trains, will be reinstated in September.
Northern said the new timetable had been designed to provide more services with its growing fleet on upgraded lines.
However a delay in the electrification of the Manchester-Preston via Bolton line meant it had to be planned and delivered in four months, compared to the "normal nine to 12 months".
The delay meant the timetable had to be totally rewritten and "significant levels" of complex driver training on new routes with different trains had to be carried out.