Yes, you can combine a travel fund (flight credit) and a credit card to pay for a flight on most major airlines, including Southwest, Delta, and United. On Southwest Airlines, for example, you can apply up to three forms of payment per passenger on a single reservation. This means you could use two separate flight credits and then pay the remaining balance with a single credit card. The system is designed to apply the "stored value" first, and then prompt you for a credit card or digital wallet (like Apple Pay) for the difference. One important caveat for 2026 is that if you use a flight credit toward a new booking and later cancel that booking, the entire value—including the portion paid by credit card—will typically be returned to you as a non-refundable flight credit rather than a cash refund to your card. Always check the "order of payment" during checkout to ensure your oldest credits (which may have expiration dates, unlike Southwest's current "non-expiring" credits) are utilized first to maximize your travel value.