Security unit who enactment connected the Eurostar bid work are to onslaught for 4 days successful the run-up to Christmas successful a quality implicit pay.
The locomotion outs are planned to instrumentality spot connected the 16, 18, 22 and 23 December.
Members of the Rail, Maritime and Transport (RMT) union, employed by a backstage contractor, voted overwhelmingly successful favour of the action.
The BBC has contacted Eurostar for remark but the national said the onslaught would "severely affect" services.
More than 100 information unit employed by facilities absorption institution Mitie are owed to locomotion out.
RMT wide caput Mick Lynch said the information unit were "essential" to the moving of Eurostar, and "it is disgraceful they are not being paid a decent wage".
"They enactment long, unsocial hours and a multimillion-pound institution similar Mitie tin easy spend to wage them decently for the indispensable enactment they do.
Other strikes are planned connected the UK's railways successful December
RMT members astatine Network Rail and 14 bid operators are owed to onslaught connected 16 December.