Analysing data spanning from January to September, experts in the aviation industry at AirAdvisor have identified the airline that exhibited the lowest reliability for UK travelers in 2025 – and it might not be the carrier you had in mind.
According to a recent analysis of figures released by the Civil Aviation Authority (CAA), TUI emerged as the least dependable airline in terms of punctuality, with only 57.5 percent of its flights departing on time, falling below the halfway mark. Conversely, a lesser-known airline shared the top position with Virgin Atlantic for the most reliable performance, boasting an 81 percent on-time departure rate.
Based on the 2025 data available, TUI showcased the poorest overall performance, earning the title of the worst airline for flight delays in the UK. Notably, other prominent airlines also experienced frustrating delays. Blue Airlines, which has ceased operations since then, closely followed TUI in the tardiness rankings, managing an on-time rate of under 60 percent in 2025. Meanwhile, Swiss Airlines slightly outperformed with approximately 64 percent of their flights operating on schedule during that year.
The top three most reliable airlines were British Airways, Wizz Air, Emerald Airlines, Lufthansa, and United Airlines; Emirates; and Loganair and Virgin Atlantic, all boasting impressive on-time departure rates. Virgin Atlantic and Loganair jointly held the title for punctuality, with 81 percent of their flights departing on time in 2025, as reported by Birmingham Live. Across all carriers, the combined average on-time performance stood at 72 percent during the same reporting period.
AirAdvisor’s study focused on the 20 airlines with the highest passenger traffic at UK airports each quarter, monitoring flight delays based on CAA records. According to CAA guidelines, a flight is considered “on-time” if it arrives at or departs from the airport gate within 15 minutes of its scheduled slot.
Anton Radchenko, CEO of AirAdvisor, highlighted that multiple factors influence an airline’s on-time performance, with past performance serving as a crucial indicator for future reliability. He noted that TUI traditionally struggles with on-time performance in quarter three, encompassing the peak holiday months of July and August. Despite a slight improvement to 55 percent in quarter three of 2025, TUI still lags significantly behind Virgin Atlantic and Loganair.
While flight disruptions are gradually decreasing in 2025, millions of passengers continue to face delays or cancellations annually. As per UK government regulation UK261, affected passengers may be entitled to compensation up to £520 based on the cause of the disruption and the notice provided by the airline.
The ranking of the worst-performing airlines, based on average punctuality from January to September 2025, provided valuable insights into the operational efficiency of major carriers during this period.