Choosing the right bag starts with understanding the Southwest Underseat Size requirements for a comfortable journey. Passengers should select a compact personal item that fits beneath the seat in front of them. Suitable options include small backpacks, handbags, laptop bags, and soft-sided totes. Measure your bag carefully, including its handles and outer pockets, before leaving for the airport. Since underseat space can vary by aircraft, reviewing the airline’s latest baggage guidelines is a smart way to avoid unexpected problems and enjoy a smoother and stress-free travel experience.