We've sent our mortgage payment certified mail every month for the past ten years (out of state bank/Fidelity, Wichita, KS) because the bank constantly lied and charged us late fees every other month, claiming it arrived one day late (first class mail). They only tried it once after we began using certified and we caught them red-handed lying. However, the tracking frequently shows the mail "out for delivery"/"available for pickup" one or two days before they sign for it. btw, three more payments and we give them the middle finger