Please be aware that Brussels and Istanbul has multiple airports and that these results are for all airports serving the city.
The best month to fly between Brussels and Istanbul is September and the most expensive month to fly is December. (Average prices, based on 342 datapoints.)
The best day to arrive at Brussels is Tuesday and it would be best to avoid Saturday, as prices are on average 86.23% higher than on Tuesday. (Average prices, based on 342 datapoints.)
The cheapest airline flying from Brussels to Istanbul is Pegasus Airlines. They are 52% cheaper than Turkish Airlines. (Average prices, based on 349 datapoints.)