Other options believed to be being considered are cutting catering on trains, which has only been partially reinstated after being suspended due to the Covid pandemic.
They come as ScotRail’s four unions today rejected a 2.2 per cent increase tied to efficiency savings.
Further talks are scheduled for Tuesday.
The Rail Maritime and Transport union (RMT) announced a strike ballot over pay on Wednesday.
Engineers in the Unite union started industrial action last Friday.
There was speculation that ticket offices under threat of closure could include Burntisland, Kinghorn and Cowdenbeath in Fife and Easterhouse in Glasgow.
Others could see their opening hours reduced, but staff would be redeployed as ScotRail has a no compulsory redundancies policy.
An industry source said ScotRail’s ticket offices had not been reviewed for at least 15 years and some were very little used.
They said the number of closures might be “very small”, perhaps as few as three.
In a report published in August, Professor Iain Docherty of the University of Stirling, the country’s leading transport academic, questioned “whether legacy business activities such as the provision of ticket offices is viable in future”.
The Transport Salaried Staffs Association said: “We are opposing this because it is likely to disproportionately affect poorer areas.
"It’s also likely to lead to an increase in anti-social behaviour.
"Booking office staff don’t just sell tickets, they also provide advice and assistance to customers – especially customers with disabilities.
"For women travelling alone, they are a reassuring presence.”
The RMT said ScotRail had also offered no increased rate for conductors working on days off, which is less than that paid to drivers because they are understaffed due to Covid delaying the training of new recruits.
That has triggered Sunday strikes by conductors since March that have halted many trains, with further action threatened during the Cop26 climate change conference in November.
An RMT memo to members seen by The Scotsman said: “Abellio ScotRail failed to table a meaningful offer at today’s pay talks.
"The company made a reckless offer of 2.2 per cent dependent on a raft of unacceptable cuts including booking office closures.
“Furthermore, no meaningful offer was tabled regarding a rest day working agreement.”
RMT Scotland organiser Mick Hogg said: “There were a whole raft of proposals under the banner of efficiency savings.”
He contrasted the offer with RMT members at ferry operator CalMac winning a 4.8 per cent increase from Friday in the second stage of a two-year deal totalling 5.4 per cent.
He said: “The $60 million question to be answered is what is the difference between a key essential ferry worker and a key essential rail worker?
ScotRail said any pay increase would have to be self-funded by “genuine efficiencies”.
Operations director David Simpson said: “We’re seeing customers gradually return to Scotland’s Railway, but the scale of the financial situation ScotRail is facing is stark.
“We will continue to engage with the rail trade unions to find an agreement on pay and conditions.
“To build a more sustainable and greener railway for the future and reduce the burden on the taxpayer, we need to change.
"All of us in the railway – management, staff, trade unions, suppliers, and government – need to work together to modernise the railway so that it is fit for the future.”