Resurrecting this thread to ask - does anyone know if it's possible to add a rail&fly ticket/voucher on United after booking? I've already purchased a ticket for LAX-FRA and need to take the train to Hannover after arriving in Frankfurt. United is listed as a "Partner Airline" for the Rail&Fly program on the DB site. However, when I called United the agent had no idea what I was talking about. They transferred me around a bit and spoke to some other agents and still didn't have any info. I know on Lufthansa and other airlines the 30 EUR voucher can be added after booking and then you redeem the voucher for a DB ticket - is this possible with United or nah?