How long is my credit valid for? October 14, 2019 23:17 Updated Follow For Standard fares the credit must be used immediately as it will expire overnight. Credit for Flexi fares will expire after 28 days. Related articles How do I get a refund? How do I change or cancel my booking? How do I get a child, student, backpacker or senior fare? Do your buses have WiFi? How do I book TranzAlpine train tickets?