Hopper includes flight options from more than 250 airlines worldwide.
However some airlines such as Southwest Airlines are not sharing their data with us currently. Additionally, Delta is no longer sharing their data with Hopper, so we're unable to include their flights at this time. We do hope that this is temporary and that we will be able to include Delta's fares again soon.
We're working hard to improve our global coverage, particularly with domestic and international low-cost carriers, and we have big plans to bring more carriers onboard soon! Stay tuned.