ScotRail will only be able to run reduced services on three lines compared to the 11 routes it has been able to operate during separate walkouts by Network Rail signallers, who are due to strike again on Saturday.
Trains will be limited to 7.30am to 6.30pm, with two an hour between Milngavie and Edinburgh via Bathgate and one an hour between Glasgow and both Lanark and Larkhall.
ScotRail said so few services would operate because a second staff member in addition to the driver was required on trains.
It told passengers: “Only travel if you really need to”.
The RMT previously rejected a 5 per cent offer with improved benefits, which is similar to the deal accepted by ScotRail’s train drivers in July.
RMT members expected to take part in Monday’s strike include train conductors and ticket examiners, station staff and cleaners.
The Scotsman understands the revised offer included an extra £500 for using new technology, additional commission for platform staff selling tickets and train crew checking electronic tickets, and a commitment to no compulsory redundancies being extended by a year to six years.
The RMT said it wanted the £500 payment doubled to £1,000.
RMT Scottish organiser Mick Hogg said: “The ScotRail RMT company council has overwhelmingly rejected the revised offer.
"We are seeking a real cost of living pay increase of 8.2 per cent.
“Therefore strike action goes ahead Monday as planned."
The union has also announced an overtime ban from Friday October 14, buts its impact remains unclear.
ScotRail said of the strike: "We are only able to provide this very limited service due to the number of contingency staff required to cover the shifts of those on strike.
ScotRail head of customer operations Phil Campbell said: “We’re really disappointed that the dispute with the RMT has reached this outcome, given the strength of the improved pay offer ScotRail made.
“This strike action does nothing for the railway’s recovery at this fragile time.
"It will severely impact our customers and it will also cost our staff through lost wages.”