Passengers can book companion passes on Southwest Airlines. To do so, travelers have to first log into their Southwest Rapid Rewards account. Then, they have to Select the desired flight and book it as usual. After booking, go to my trips section and click Add a Companion. Further, enter the companion’s details and pay the applicable taxes and fees. Moreover, one can also avail of the Southwest Companion Pass flight by speaking to a live person at customer service or the check-in counter at the airport. This service lets companions fly free of cost whenever passengers book or redeem a point to get a pass.