Passengers flying from Dublin Airport are being advised to arrive two hours before short-haul flights and three hours before long-haul flights as a result of a "significant improvement" in security screening queue times.
For passengers checking in a bag, it is advised that they allow an additional time of up to an hour.
In a relaxation of the recommendations from the airport's management body the DAA, passengers are also being advised to allow an additional time of up to an hour for check-in luggage.
The previous advice from Dublin Airport was for passengers to arrive two-and-a-half hours before a short-haul flight three-and-a-half hours before a long-haul flight.
Dalton Philips, chief executive of DAA, said: "During July - Dublin Airport's busiest month in three years - over three million passengers flew in and out of the airport.
"99% of all passengers passed through security in under 45 minutes, while 90% of passengers queued for 30 minutes or less.
"In the first two weeks of August, virtually all passengers were through security screening in 30 minutes or less."