At the moment, there are zero airlines flying to Istanbul. Go through the results to find the right flights for you – you can adjust the filters to see find even more flights to Istanbul.
If you want to broaden your search, look at flights departing from other airports.
The distance between London Stansted to Istanbul is 2520 km. You can see the various flight times in the results.
Searching by month, for instance, will show you the best time of the week to fly.