One passenger told the BBC she waited for two hours at passport control, another said after a flight from Cork she waited so long they were put into another area.
Other passengers expressed their frustration on Twitter.
Sophie Elliot posted on the social networking site: "Last night at Stansted we were trapped in queues of over an hour - longer for the people behind us - cos 'a few planes landed early'."
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Public sector organisations will have to publish information on any gender pay gap from Friday, in a bid to tackle discrimination.
Remarkably mild night for March