Southwest is the best of a relatively bad lot of US airlines when it comes to delivering a high-quality experience to customers, according to a new UserTesting report.

The Airline Customer Experience Index report, ranked Southwest first primarily due to the speed and ease with which travellers could access flight information and perform other tasks, such as calculating the final cost of a flight including baggage.

Other metrics weighed into the rankings included the aesthetics of airlines’ websites, their perceived credibility, and the extent to which their online experience “delighted” customers by meeting or exceeding customers’ needs.

The report — based on a survey of 1,000 travellers who interacted with the airlines via the internet, and released September 7, 2017 — found that even Southwest met but did not exceeded customers’ expectations.

“As customers are primed to expect excellence from the companies they interact with the most, merely providing a positive experience is not enough to delight them,” the report noted.

“Overall customer experience performance from the top 12 North American airlines was dismal, with the top four performers achieving only “Okay” scores. In fact, not one airline received “Good” or “Excellent” scores,” according to the report.

Alaska, American, Delta, Frontier, Hawaiian, JetBlue, Southwest, Spirit, United, and Virgin America were the airlines included in the report.

Virgin America finished second in the rankings with a score of 81.7, trailing only Southwest’s 86.9. Spirit was the lowest ranked airline, with a score of 36.4 — far worse than any other airline in the report.

For example, while Southwest received a score of 73.1 for the ease of calculating the final cost of a flight with two checked bags, Spirit’s score was a nearly undetectable 0.5.