New data reveals worst U.S. airlines for delays, cancellations

Newly released federal data on airline performance is offering a clearer picture of which U.S. carriers are most likely to cancel flights, run late and test travelers’ patience, even as overall reliability has improved since the pandemic era.

Federal reports show gaps widen between best and worst carriers

According to the U.S. Department of Transportation’s Air Travel Consumer Reports and related Bureau of Transportation Statistics data, cancellation rates across the largest U.S. carriers have stabilized at roughly 1.3 to 1.5 percent of scheduled flights in recent full-year measurements. That is significantly lower than the disruption-heavy years immediately following the pandemic, when cancellations were closer to 3 percent of operations.

Beneath the national averages, however, performance varies sharply by airline. Recent annual rankings compiled from federal on-time performance and cancellation statistics show that the most reliable carriers cancel less than 1 percent of their flights, while those at the bottom end post cancellation rates closer to 1.7 to 2 percent and experience substantially more late arrivals.

Industry analyses that combine government statistics with proprietary tracking data indicate that United, Delta, Alaska and certain smaller niche carriers such as Hawaiian and Allegiant typically appear near the top of recent rankings for completion factor and on-time arrivals. At the other end of the spectrum, ultra-low-cost carriers, along with some regional operators flying on behalf of major brands, tend to report higher disruption rates.

These divergences have concrete implications for travelers. On a network that collectively operates millions of flights a year, a difference of even half a percentage point in cancellation rate can translate into thousands of additional scrubbed flights and hundreds of thousands of affected passengers.

Which airlines rank worst for cancellations

The most recent full-year summary tables published in the federal Air Travel Consumer Reports, covering calendar years 2024 and 2025, show wide variation in cancellation rates among the 14 reporting U.S. carriers. Allegiant, United, Hawaiian, Southwest and Delta recorded some of the lowest cancellation percentages, all near or below 1 percent of operations in the latest data.

By contrast, several airlines landed at the bottom of the pack. Frontier and Spirit, two of the largest ultra-low-cost carriers, reported cancellation rates in the range of roughly 1.5 to 1.8 percent in the latest year-by-year tallies, noticeably above the national average. Among regional airlines, Republic Airways and PSA Airlines posted some of the highest cancellation shares, exceeding 3 percent and 4 percent of scheduled flights respectively in the most recent full-year tables, marking them as outliers in terms of reliability.

Consumer-facing ranking projects that synthesize those federal statistics into scorecards of “best and worst airlines” generally place these same names near the bottom when evaluating cancellations alone. While methodologies differ, most of these studies assign lower scores to carriers with above-average cancellation percentages and factor in how consistently those disruptions affect travelers over a 12-month period.

Experts note that regional carriers’ results directly affect customers of the major brands whose tickets they fly under. When a regional operator with a higher cancellation rate serves as a feeder for a major network, passengers may experience more frequent last-minute cancellations even if the mainline brand’s own aircraft are performing relatively well.

Delays remain widespread, with some carriers standing out

While cancellations have moderated, delays remain a persistent feature of U.S. air travel. Aggregated data from the Bureau of Transportation Statistics show that national on-time performance in recent years has hovered around the high 70 percent range, meaning roughly one in five flights arrives 15 minutes or more behind schedule.

Third-party analyses built on those federal feeds show that the same ultra-low-cost and certain regional carriers that struggle with cancellations often also see higher delay rates. Carriers such as Frontier, Spirit and JetBlue frequently post some of the lowest on-time percentages in comparative rankings, with substantial shares of their flights arriving late.

Network airlines like Delta, Alaska and United usually score better than the national average on punctuality, although performance can fluctuate by season and hub. Severe weather, congested airspace and crew availability continue to drive delays across all carriers, but analysts point out that staffing buffers, fleet flexibility and schedule design can either magnify or mitigate those pressures.

Recent academic work examining system-level airline performance from 2022 through 2024 concludes that while macro factors such as weather and air traffic control constraints play a major role, differences in operational planning and resource allocation among carriers still explain much of the gap between the most and least punctual airlines.

Complaints reveal how travelers experience delays and cancellations

Operational statistics tell only part of the story. Complaint data released by the Department of Transportation show that passenger frustrations have remained elevated even as cancellation rates declined from their pandemic-era peak. In 2023, for example, federal officials reported that overall consumer grievances against airlines were still significantly higher than pre-pandemic norms, with flight problems, including delays and cancellations, accounting for the largest category of complaints.

Analyses by consumer advocacy groups that review this complaint data have repeatedly identified Frontier as receiving the highest rate of grievances among U.S. carriers in recent years, with American and United also drawing large numbers due to their scale. While complaints do not always map directly to operational metrics, they offer another lens into where passengers perceive service to be falling short.

Researchers caution that only a fraction of dissatisfied travelers file formal complaints with federal agencies, meaning the published numbers likely understate the true volume of frustration. Still, comparing complaint figures with on-time and cancellation data helps highlight patterns. Airlines that combine relatively high disruption rates with limited customer service responsiveness or compensation policies often generate the most negative feedback.

This dynamic has attracted growing regulatory scrutiny. Recent rulemaking efforts have focused on clarifying what passengers are owed during disruptions caused by airlines, including refunds and fee-free rebooking when flights are significantly delayed or cancelled for reasons within carriers’ control.

What travelers can do with the new rankings

For travelers, the latest rankings of airline performance on cancellations and delays offer practical guidance but not absolute guarantees. Consumer advocates recommend treating the worst-ranked carriers as higher-risk options, particularly for time-sensitive trips such as weddings, cruises or important business meetings, where a disruption could have costly knock-on effects.

Experts suggest that when routes allow, passengers who prioritize reliability may want to favor carriers that consistently appear near the top of federal on-time performance tables, especially during peak travel months when the system is under the most strain. Building extra connection time into itineraries, opting for earlier departures where possible and avoiding tight layovers at congestion-prone hubs can also reduce the risk of missed flights.

At the same time, analysts note that even top-ranked airlines experience significant delays during severe weather or nationwide system disruptions. The latest data indicate that choosing a carrier with a stronger record on cancellations and punctuality improves the odds of a smooth trip, but does not eliminate the possibility of disruption.

With new federal consumer reports and independent studies being updated regularly, travelers now have more information than ever to compare airlines on reliability. Those rankings are increasingly shaping booking decisions, as fliers weigh low fares against the potential hidden costs of getting stranded by a cancelled or severely delayed flight.