New analysis of official data has revealed the airline that attracts the most passenger complaints in the United Kingdom, and it is not one of the nation's most prominent low-cost or flag carriers. The findings, based on Civil Aviation Authority (CAA) statistics, paint a detailed picture of consumer dissatisfaction within the UK aviation sector over a recent ten-month period.
Wizz Air Tops the Table for Passenger Grievances
Scrutiny of the CAA's most recent figures, covering mid-2024 through March 2025, identifies Wizz Air as the airline with the highest complaint rate. The Hungarian carrier received a total of 10,548 customer grievances during this timeframe. When calculated per million passengers carried, this equates to a staggering 918 complaints, a figure that significantly outpaces its competitors.
This performance places Wizz Air firmly at the top of an unwanted ranking, surpassing other airlines known for high passenger volumes. The data indicates that for every million travellers who flew with Wizz Air, just under one thousand individuals formally lodged a complaint with the UK's aviation regulator.
How Other Major Airlines Compare
The analysis provides a clear comparison with other significant operators in the UK market. British Airways, the UK's flag carrier, recorded a substantially lower grievance rate of 192 complaints per million passengers. However, when complaints were investigated, a much higher proportion—83%—were upheld in favour of the passenger.
In a result that may surprise frequent flyers, Ryanair did not attract the highest number of complaints relative to its passenger numbers. The low-cost giant's complaints-per-million-passengers figure stood at 188, with a comparatively modest upheld rate of 28%.
Context of a Turbulent Period for Aviation
This complaint data emerges against a backdrop of significant operational challenges for the airline industry. The first five months of 2025 were particularly difficult, blighted by tens of thousands of delays and cancellations across Europe.
According to separate reports, airlines like KLM, British Airways, and Lufthansa cancelled thousands of flights during this period. Finnish carrier Finnair recorded the highest proportion of cancelled services, grounding 3.35% of its scheduled trips. This context of widespread disruption likely contributed to the overall volume of passenger grievances.
Breakdown of Complaint Outcomes and Compensation
The CAA data not only reveals complaint volumes but also details the outcomes and financial compensation involved. For Wizz Air, 47% of the complaints lodged were upheld in the passenger's favour. The airline disbursed a total of £1,482,183 in compensation, averaging £651 per successful claimant.
By contrast, British Airways distributed a much larger total sum of £6,238,378, reflecting its higher upheld rate, with an average payout of £837 per customer. Ryanair's average compensation stood at £694 per upheld complaint.
The Most Complained-About Airlines: A Detailed Snapshot
The full data set provides a ranked list of airlines operating in the UK based on complaints per million customers, alongside their complaint upheld percentage and average award.
- Wizz Air: 918 complaints per million; 47% upheld; £651 average award
- Air France: 301 complaints per million; 43% upheld; £828 average award
- Turkish Airlines: 265 complaints per million; 51% upheld; £718 average award
- Egypt Air: 234 complaints per million; 19% upheld; £630 average award
- TUI: 223 complaints per million; 20% upheld; £722 average award
- British Airways: 192 complaints per million; 83% upheld; £837 average award
- Ryanair: 188 complaints per million; 28% upheld; £694 average award
- Air Portugal: 171 complaints per million; 37% upheld; £662 average award
- EasyJet: 147 complaints per million; 18% upheld; £630 average award
The CAA's role is crucial in this process. Provided a flight departs from or arrives in the UK, passengers are entitled to lodge a formal complaint with the Authority regarding a wide range of issues. The most frequent grievances cited in the data include flight disruptions, denied boarding, lost or damaged luggage, and inadequate assistance for disabled passengers.
Over the ten-month period analysed, more than 43,000 complaints were formally lodged about airlines operating in the UK, underscoring the scale of passenger dissatisfaction and the importance of robust consumer protection in the aviation sector.
