Thursday is the busiest day for air travel ahead of Christmas, according to the Federal Aviation Administration. However, Friday and Saturday will be the busiest days for holiday travel for United Airlines at Newark Liberty International Airport.

More travelers than ever before are heading out closer to the holiday, which will keep United employees busy. During this holiday travel period, United is expecting to fly almost 9,000,000 customers nationwide, beginning Thursday and continuing through Jan. 8 — this is about 4,000 flights per day.

United customer service representative Cyrus Sarkari says United expects to have almost 1,000,000 people fly just on Friday and Saturday alone.

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United officials told News 12 New Jersey that Tuesday, Jan. 2 will be one of its busiest return dates for travel.

Also, AirTrain service at Newark Liberty International Airport fully resumed after the service was on a modified service Thursday morning.