San Antonio, TX 78269-2408. Or Fax to (866) 493-1441.Virtual Branch provides you with the flexibility to handle your transactions and inquiries without having to visit or call. Gov and must be legible. The mortgage payoff calculator helps you find out. See what you can afford. Find out in minutes how much you could borrow and receive a customized mortgage estimate — all without affecting your credit score. Mortgage loan options can fit your needs. Compare mortgage loans and rates with RBFCU. Our Member Advisors and Advocacy Team is ready to serve your needs at your convenience.