Get round-trip flights on Southwest Airlines with rates from $124 on Airfarewatchdog. We found the lowest fares on flights between Detroit to Dallas. Sunday fights from New York to Miami start at $136, and flights from Orlando to Chicago start at $189. You can enter your own travel dates and locations to find fare prices on Airfarewatchdog. Some of these flights need to be booked at least 21 days in advance and require travel on specific days of the week. Prefer to book a vacation package with the airline? There's a resort promotion going on at Southwest Vacations, too. Taxes, fees, and restrictions may apply.