This means that if you’re accepted, you will be able to choose one person to fly with you, free of airline charges, throughout the year. While the actual ticket fare may be wavied, you will still be expected to pay the taxes and fees that amount from $5.60 one-way.
To earn this Companion Pass and 30,000 points, however, you’ll have to first spend $4,000 on the card within the first three months of opening it. The pass is also only usable until December 31, 2019, and can only be applied for until February 11, 2019. So if you want to qualify and take advantage of the benefits, you’d better hurry.
Prior to the promotion, the passes were only available to travelers who had completed 100 qualifying flights or earned 110,000 qualifying points with Southwest Airlines in one calendar year, making it nearly impossible to obtain one.
To qualify, you can’t currently hold a personal Southwest credit card, or earned a sign-up bonus from a Southwest card in the past 24 months. 
H/T: Travel & Leisure