The Unite union announced on Friday that around 300 workers at Gatwick will strike over pay this July.
The strike involves baggage security screeners, employed by ICTS and 200 workers who provide special assistance services, employed by Wilson James.
Both sets of workers have rejected pay offers and plan to strike from 12 to 14 July and 19 to 21 July. With further industrial action possible if disputes are unresolved.
Unite general secretary Sharon Graham said: "These workers undertake incredibly demanding roles at one of the UK's busiest airports. They are simply seeking a fair day's pay.
"ICTS and Wilson James are wealthy companies and can well afford to put forward acceptable pay offers. Our members at Gatwick have Unite's total backing in taking strike action for a decent pay rise.
The strikes will cause significant disruption to security screening and passenger services.
Additionally, HGV drivers and warehouse workers for Dnata, who provide onboard catering for Easyjet, are being balloted for potential strike action over shift pay.
Unite regional officer Dominic Rothwell said: "The employers in these disputes are responsible for any disruption caused to passengers at Gatwick. These disputes could be easily resolved if reasonable offers are put forward.
"There is still time to avoid industrial action, but that will require these companies to table deals that are acceptable to our members."
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