Northern has cancelled about 80 rail services on Sunday and expects to abandon more, as some train staff have "made themselves unavailable".
The firm apologised for the disruption, which will mainly affect Liverpool, Lancashire and Greater Manchester.
Staff contracts mean employees do not have to work on Sundays if they provide seven days' notice.
It follows similar disruption across the network on the day of the World Cup final on 15 July.
Chaos on the Northern network, caused by a new timetable's introduction in May, has been the subject of much passenger misery this summer.
Services resumed earlier this week after the operator ended up cancelling 165 daily train services until the end of July.
Speaking about the Sunday cancellations, a Northern spokesman said: "Unfortunately we have so far had to cancel around 80 services across our network and it is likely more will be cancelled as we continue to plan our services.
"On each route, customers will either have other rail options via Northern and other operators or will have the provision of rail replacement transport."
Commuters have been advised to check the operator's website or National for updates.
Details of planned cancellations for Sunday
- Liverpool to Manchester Airport - full cancellation
Northern customers will still be able to travel between Liverpool and Manchester using Northern services or East Midlands Trains. Trans Pennine Express services are available between Manchester Piccadilly and Manchester Airport.
- Wigan North Western - Liverpool - 50% of services cancelled
One service per hour will run between Liverpool Lime Street and Wigan North Western.
- Blackpool South - Colne and Blackpool - Carlisle
Northern will operate one train every two hours between Blackpool South and Colne. Rail replacement buses will be provided in place of cancelled services.
Both Dalesrail services between Blackpool and Carlisle are cancelled.
- Lancaster - Morecambe
There will be two part cancellation between Morecambe and Heysham Port. Taxis will be provided for customers travelling between the port and Lancaster.