You cannot "merge" two people into a single Southwest Rapid Rewards account; every traveler, including your spouse, must have their own individual account number. However, you can effectively "add" them to your travel benefits through the Southwest Companion Pass. This is widely considered the best deal in travel: once you earn enough points (135,000) or fly 100 segments in a year, you can designate your spouse as your "Companion." To do this, log in to your account on Southwest.com, find the "Choose Your Companion" section in your Snapshot tab, and enter their details. Once they are your Companion, they fly with you for just the taxes and fees ($5.60) on any flight you book, whether you paid with cash or points. If you aren't at Companion Pass status yet, the best way to manage travel together is to ensure both your Rapid Rewards numbers are in the same reservation ("Linked") so that your boarding positions are assigned together and your points are tracked accurately for your respective accounts.