Southwest Airlines will pay a $35 million fine as part of a $140 million agreement to settle a federal investigation into cancelling thousands of flights and stranding over 2 million travelers in December 2022 over the holidays. Most of the $90 million settlement will go towards compensating future passengers through travel vouchers and is the largest penalty the US Department of Transportation has ever imposed on an airline for violating consumer protection laws. In addition to the fine, Southwest will get $33 million in credit for compensation already provided to customers, such as frequent flyer points worth $300 each to affected travelers.