RMT members working across 14 train operating companies have announced three strike dates for next month.
20,000 railway workers will walk out on 20, 22 and 29 July after train operators failed to make a new pay offer.
Mick Lynch, RMT general secretary, said: "This latest phase of action will show the country just how important railway staff are to the running of the rail industry. My team of negotiators and I are available 24/7 for talks with the train operating companies and government ministers.
"Quite incredibly neither party has made any attempt whatsoever to arrange any meetings or put forward a decent offer that can help us reach a negotiated solution."
Members voted by 9-1 to renew their strike mandate, Lynch said.
He added: "RMT will continue its industrial campaign until we reach a negotiated settlement on pay, working conditions and job security."
It comes after the RMT in April announced strikes on 12 May, 31 May and 3 June, the same day as the FA Cup final.
UKHospitality estimated the cumulative effect of the series of strikes between last autumn and earlier this spring cost the sector £3.25b. Kate Nicholls, chief executive of UKHospitality, has urged the unions and train companies involved to conduct "constructive discussions to reach an agreement" due to the critical nature of the hospitality industry to the public and workers.