Yes, you can combine multiple Southwest Flight Credits (formerly known as travel funds) to pay for a single new reservation, but there is a technical limit of three forms of payment per passenger, per transaction. This means you can use up to three individual flight credits to cover the cost of a flight. If the total of those three credits doesn't cover the full fare, you will only be able to use two credits and then use a credit card for the remaining balance. It is important to remember that since 2022, Southwest flight credits do not expire, providing much more flexibility than in the past. If you are looking to combine funds for a trip involving multiple people, keep in mind that standard flight credits are non-transferable and can only be used by the passenger whose name was on the original ticket. However, "Transferable Flight Credits" (available with certain fare classes like Wanna Get Away Plus) can be moved to another Rapid Rewards member's account.