Amtrak Promo Codes (29) - November 2022 - RailServe.com Amtrak Promo Code: Book at Amtrak.com: Save 20% to North Carolina Expiration: Book by January 30, 2024. Travel by January 31, 2024. Amtrak Trains/Routes: Carolinian and Piedmont trains and associated Thruway buses within North Carolina only. Advance Ticket Purchase Required: One day. MIDWEST Amtrak Promo Code Discounts for 2022