Their 20 busiest routes during the two month period from mid-June to mid-August, had the following outcomes: 71% flights arrived on time, 14% were classed as late, 6% very late and 6% were excessively late, with zero cancellations according to FlightStats.

Turkish Airlines generally maintains a strong on-time performance (OTP) record, often ranking among the top major European and global carriers. In 2025 and early 2026, the airline has reported OTP rates consistently in the 75% to 85% range. However, because their primary hub, Istanbul Airport (IST), is one of the busiest and largest in the world, delays can occur due to its sheer scale and the complexity of its massive connecting network. Weather-related delays in Istanbul (especially fog or wind) can also create "knock-on" effects for their global schedule. While they are not considered "often late" compared to the industry average, the high volume of connecting passengers means that even a 20-minute delay can feel significant if you have a tight connection. Passengers are generally advised to leave at least 90 minutes to 2 hours for transfers at IST to account for the long walking distances between gates and any minor flight timing adjustments.