The second in a planned series of six consecutive Sunday stoppages by the Rail, Maritime and Transport union (RMT) is expected to trigger the cancellation of 510 of 1,090 services that would normally run – or 47 per cent.
It means no ScotRail trains on lines across the Highlands, Aberdeenshire, Tayside, the Borders and Dumfries and Galloway.
The operator’s only trains in Edinburgh are expected to be on the line to Glasgow Queen Street re Airdrie and Bathgate, which are staffed by ticket examiners rather than conductors.
The conductors’ walkout is over a long-running dispute about being paid less then drivers from working on days off.
It is due to continue every Sunday until May 2.
Trains cannot operate without conductors, who control the doors, and ScotRail has been unable to train managers to stand in because of Covid restrictions.
However, the disruption could be widened to the whole of ScotRail if ticket examiners vote next week to take industrial action as well.
They check tickets on most suburban trains in the Glasgow area and on five Ayrshire and Inverclyde lines, with drivers controlling the doors.
All four ScotRail unions announced this week they were considering a separate strike ballot over pay.
Unison its already balloting its engineering members over the issue and payments for working on days off.
No trains will run on Sunday on these routes:
Aberdeen – Glasgow/Edinburgh
Aberdeen – Inverurie/Inverness
Aberdeen – Perth/Dundee
Edinburgh – Inverness/Aberdeen
Edinburgh – Inverkeithing/Glenrothes/Kirkcaldy/Perth/Dundee
Edinburgh – Stirling/Dunblane
Edinburgh – Tweedbank
Edinburgh – North Berwick
Edinburgh – Glasgow Central via Shotts
Glasgow – Edinburgh via Falkirk High
Glasgow – Anniesland
Glasgow – Stirling/Alloa/Dunblane/Perth/Dundee
Glasgow – Inverness/Aberdeen
Glasgow – Cumbernauld
Glasgow – Alloa
Glasgow – Barrhead/Kilmarnock/Dumfries/Carlisle
Glasgow – Stranraer
Glasgow – Crainlarich/Oban/Fort William/Mallaig
Inverness – Aberdeen/Edinburgh/Glasgow
Inverness – Kyle of Lochalsh/Wick
Limited buses wil run for key workers to University Hospital Hairmyres in East Kilbride, Queen Margaret Hospital in Dunfermline and Victoria Hospital in Kirkcaldy.
ScotRail said anyone who had already bought a ticket could travel on Saturday or Monday instead, or could request a refund.