The best month to arrive at Islamabad is September and the most expensive month to fly is March. (Average prices, based on 1903 datapoints.)
The best day to arrive at Islamabad is Friday and it would be best to avoid Tuesday, as prices are on average 22.53% higher than on Friday. (Average prices, based on 1695 datapoints.)
The cheapest airline flying to Islamabad is PIA. They are 50% cheaper than Saudi Arabian Airlines. (Average prices, based on 1910 datapoints.)