The company’s 2021 North America Airline Satisfaction Study measured passenger satisfaction with airline carriers in North America based on performance in eight categories: aircraft, baggage, boarding, check-in, cost and fees, flight crew, in-flight services, and reservations. J.D. Power surveyed 2,309 passengers—a mix of both business and leisure travelers—who had flown on a major North America airline within the past month of completing the survey. J.D. Power then used those results to calculate the Overall Passenger Satisfaction Ranking for each airline, based on a 1,000 point scale. The research was conducted from August 2020 through March 2021 and then published in May. At Best Life, we only looked at airlines in the U.S. and excluded those based in Canada to figure out which one is the most unreliable here. Read on to find out which major airline left travelers unhappiest, making it the least trusted of them all! RELATED: The Least Trusted Major Airport in the U.S., According to Customers. J.D. Power customer satisfaction score (out of 1,000): 860 In addition to receiving the highest score on J.D. Power’s 2021 North America Airline Satisfaction Study, Delta also received top marks in the American Consumer Satisfaction Index (ACSI) 2020-2021 Travel Report. The airline received a 79 out of 100, a tie with Southwest for the highest score of all nine airlines in the report. “Thank you for making good on your cancellation policy,” one verified reviewer wrote on Consumer Affairs. “Using the chat feature on the website was fabulous! I knew I could count on Delta for great customer care. Will be using Delta as much as possible from now on. If only there were people who wanted to work customer service on your phone lines, you would have a home run.” RELATED: This Is the Most Unreliable Car in the U.S., Owners Say. J.D. Power customer satisfaction score (out of 1,000): 856 Southwest tied for first with Delta on the ACSI ranking and had the second highest score on the J.D. Power study. And while its recent announcement that the airline would extend its ban of alcoholic beverages on flights for the rest of the year may have an impact on consumers’ opinion of the airline, right now people seem pretty satisfied with Southwest. “Southwest Airlines is one of the top airlines that I trust. Their customer service is unmatched,” according to one verified Consumer Affairs reviewer. “I always feel safe and secure when traveling with them. In having a peanut and tree nut allergy, they always provide a snack that I am able to enjoy without compromising my health. Their employees ensure that all of my questions are answered and they always enforce safety precautions.” J.D. Power customer satisfaction score (out of 1,000): 849 JetBlue has made a name for itself for offering more legroom and better snacks than its competitors, but even though the airline had the third-highest score here, and performed fairly well on the ACSI survey, scoring a 77, it seems the company is not without its unsatisfied customers.ae0fcc31ae342fd3a1346ebb1f342fcb “Our flight was delayed over 2 hours and we missed the connection with 2 other flights in succession,” one dissatisfied traveler wrote in a review on Trustpilot. “There was no warning on the website when we tried to check in, so we reached the airport and the first person who told us the problem was very unfriendly.” J.D. Power customer satisfaction score (out of 1,000): 835 Alaska Airlines finds itself in the middle of the pack in J.D. Power’s study. It’s not the best, it’s not the worst, but it could definitely use some improvements in the customer service department. “They say one thing on the phone and then deny saying it when you miss your flight,” a verified Consumer Affairs reviewer wrote in March 2021. “They did not follow safety guidelines about capacity. The manager on the phone was dismissive and did not start the refund like he said.” J.D. Power customer satisfaction score (out of 1,000): 810 Nothing throws a wrench into your travel plans more than a canceled flight, but what can make it even worse is the failure of the airline to be as accommodating as possible. And that’s precisely the problem some travelers seem to have with United. “This is the 4th time in the past two years that United has canceled my flights within an hour of departure, with no explanation, and offered no compensation,” a verified United customer wrote in a recent Skytrax review. “When I tried to speak to someone at San Francisco International about the issue, she then lied to me and told me they do not have a customer service department, and that there are no refunds given for canceled flights, ever.” For more rankings and travel tips delivered straight to your inbox, sign up for our daily newsletter.  J.D. Power customer satisfaction score (out of 1,000): 791 Of the U.S. airlines on J.D. Power’s 2021 North America Airline Satisfaction Study, American Airlines received the lowest score. American is another carrier, along with Southwest, that recently announced that it will continue to ban the sale of alcoholic beverages on board its flights until at least 2022. But a lack of booze isn’t the only thing that American passengers are unhappy with. “Flight delayed from 11:00 AM to 5:45 PM. We stayed on the plane for 2 hours with multiple engine failures,” a verified angry American Airlines passenger wrote in a recent Skytrax review. “After finally deplaning us, we had to wait for new pilots, which took about another hour or two. Then we were told the cabins were too hot and needed to cool down which took another 2 hours. We were told little to nothing and received no help or vouchers. Staff was rude and told us to be nice because they extended their work days for us. Not even acknowledging a literal 6+ hour delay, which caused the majority of every passenger to miss plans, and left me and my partner without a ride.” RELATED: Major Airlines Are Now Banning This One Type of Mask.