Contracted out cleaners will take national strike action for the first time on 22 23, and 31 December.
Over 1,000 contracted out cleaners working for the likes of Churchill, Atalian Servest and Mitie are eligible to take walkout.
Cleaners are demanding £15 an hour, company sick pay, decent holidays and good pensions from contractors - some of whom are raking in profits of over £100 million a year.
Rail companies who use contracted out cleaning providers such as Avanti West Coast, GWR, LNER and TransPennine Express will be affected by the action.
RMT general secretary Mick Lynch said: "Cleaners are an integral part of our railways and it is a national disgrace that many languish on the minimum wage, with no company sick or holiday pay, when they were rightly considered heroes during Covid.
"These companies are raking in millions of pounds worth of profit, and it is high time they handed over a chunk of that money to their hard-working staff rather than rewarding greedy shareholders.
"Ultimately all contracted out services should be brought back in-house and we will fight tooth and nail for pay justice for our people in this industrial campaign."