If you booked on their website, sign in to your account and locate your reservation (click on My Account to see your reservations). Select "Change flight" and continue as if you were booking a new reservation. Check the same date and flight originally reserved, if you are not changing that, and keep clicking "continue," till you see the "Air Itinerary and Pricing" page. There, you will see the current fare for your flight. DO NOT accept, unless that current fare is lower than your original ticket. If it's higher, either just close the page or go back. If it's lower, then accept. Your savings will be held as a credit to be used for future travel, which must be completed within one year from date of original purchase. Make sure that you keep a record of that confirmation number and amount of credit. You must know this to book your future flight for which you want to use that travel funds balance. BTW, only the person named on the original ticket can use that credit. There is no fee or charge for re-faring on Southwest.If I book a Southwest Flight paying in Dollars (not points) and the cost goes down - can I get that $$ back (even as a SW "credit")? How would I do that?