
Sometimes airline flights are delayed due to bad weather. Other times, however, they are delayed because, well, no one seems to know why.
If you’d like to do everything you can to avoid the prospect of a flight delay or cancelation, there’s some good news. New research shows that your choice of airline directly factors into whether or not your flight may be delayed or canceled. In other words, some airlines are more prone to delays and cancelations than others.
The staff at the Family Vacation Guide began researching flight information to determine which airlines are most likely to experience flights that are delayed or canceled so you may be able to plan a trip accordingly.
To do that, Family Vacation Guide analyzed data compiled by the U.S. Department of Transportation’s Bureau of Transportation Statistics (BTS). According to the BTS report, which was compiled from data recorded between July 2019 and July 2021, a flight is considered delayed when it arrives 15 or more minutes later than the schedule.
Based on its findings, Family Vacation Guide compiled a list of the airlines with flights most likely to be delayed or canceled. As the report’s authors note, “It perhaps comes as no surprise that the three airlines with the highest percentage of late arrivals are all low-cost carriers.”
Let’s get right to the list. Here are the 10 U.S. airlines most likely to experience a flight delay.
1. Allegiant Air
Allegiant, which is based in Las Vegas, explains that it offers flights from small and medium cities to vacation destinations at “industry-low average fares.” The airline, which is the official airline of the NFL’s Las Vegas Raiders and is the naming rights partner for Las Vegas’ Allegiant Stadium, offers nonstop flights to locations throughout the U.S., as well as service to Canada and Mexico.
More than a quarter of those flights were delayed or canceled. In fact, 27.31 percent of the airline’s flights were delayed, while just 72.69 percent of its flights were on time, according to Family Vacation Guide’s research.
2. JetBlue Airways
Based in New York City, JetBlue was the seventh-largest U.S. airline by number of passengers in 2020, carrying 14.31 million passengers. The airline serves more than 100 destinations across the U.S., Caribbean, and Latin America, principally flying out of hubs in New York City, Boston, Fort Lauderdale-Hollywood, Los Angeles, Orlando, and San Juan.
Family Vacation Guide’s research found that 23.20 percent of the airline’s flights were delayed or canceled while 76.9 percent of the flights were on time.

3. Frontier Airlines
Headquartered in Denver, Frontier explains that it is committed to “Low Fares Done Right” and that the company’s employees are “tireless in our efforts to save you money on your flights.” The airline serves approximately 120 destinations in the U.S., Canada, Caribbean, Mexico, and Central America.
More than 21 percent of the airline’s flights were delayed or canceled. Conversely, just under 79 percent (78.76) of Frontier’s flights were on time, Family Vacation Guide reports.
4. Envoy Air
Originally founded as American Eagle Airlines, Envoy Air is a wholly owned subsidiary of American Airlines Group. Headquartered in Irving, Texas, the airline offers regional flight service for American through American’s hubs such as Dallas/Fort Worth, Chicago, Miami, and Los Angeles. It offers approximately 1,000 daily flights to more than 150 destinations.
Family Vacation Guide’s research found that nearly one-fifth (19.52 percent) of Envoy’s flights were delayed or canceled while 80.48 percent of the flights were on time.
5. United Airlines
Based in Chicago, United was the fourth-largest U.S. airline by number of passengers last year, carrying 37.99 million travelers. The airline offers 3,118 flights each day to 252 U.S. cities as well as 80 international locations. Much of that traffic departs its hubs in Chicago, Denver, Houston, Los Angeles, Newark, San Francisco, and Washington, D.C.
Of those flights, 81.40 percent were on time and 18.6 percent of the flights were delayed, Family Vacation Guide explains.

6. American Airlines
Founded in 1930 and headquartered just outside Dallas/Fort Worth, Texas, American was the second-largest U.S. airline based on number of passengers in 2020. Indeed, last year, 65.85 million people traveled on the airline. The airline, with its regional partner American Eagle, offers 6,700 flights each day to 350 destinations in 50 countries.
Family Vacation Guide’s research points out that 18.55 percent of those flights were delayed while 81.45 percent were on time.
7. Spirit Airlines
Spirit explains that it offers flights to more than 60 destinations at “ultra low fares.” Those flights include locations in the U.S. as well as the Caribbean and Latin America. Based in Miramar, Florida, in the Miami metro area, Spirit was the sixth-largest U.S. airline by number of passengers last year, carrying 18.44 million passengers.
Just over 82 percent of its flights were on time last year, while 17.96 percent of its flights were delayed, Family Vacation Guide notes.
8. Southwest Airlines
Dallas-based Southwest was the largest U.S. airline by number of passengers last year — carrying 69.65 million passengers. The airline notes that in 2019, it offered more than 4,000 weekday departures to 101 U.S. destinations as well as destinations in 10 other countries.
Of those flights, slightly more than 83 percent were on time. Then again, just under 17 percent of its flights were delayed, Family Vacation Guide’s study explains.

9. Alaska Airlines
Alaska Airlines, which is based in Seattle, and its regional partners serve more than 120 destinations across the U.S., as well as Canada, Mexico, and Costa Rica. The airline announced earlier this week that it will begin offering daily nonstop flights from Seattle-Tacoma to Miami next year. That announcement means Alaska Airlines will serve 100 destinations with nonstop flights.
Family Vacation Guide’s research found that slightly more than 83 percent of the airline’s flights were on time while just under 17 percent of its flights were delayed.
10. SkyWest Airlines
SkyWest Airlines was the fifth-largest U.S. airline by number of passengers in 2020, carrying 20.36 million passengers. The airline points out that in 2019, however, it carried more than 43 million passengers through its partnerships with United, Delta, American, and Alaska Airlines. SkyWest Airlines, based in St. George, Utah, offers services to 236 cities in the U.S., along with destinations in Canada and Mexico.
Slightly more than 84 percent of the airline’s flights were on time last year, Family Vacation Guide found. The flip side of the coin is that 15.99 percent of its flights were delayed.
While you’re thinking of it, be sure to read the rest of our airports and flying coverage, including: