Booked a ZFV-EWR-XXX flight for an astoundingly low price. Checked in on UA desktop site 24 hours before departure and I received boarding pass (in PDF) in two pages:

1. page 1 was EWR-XXX with standard UA boarding pass (this was UA metal)
2. Page 2 was the ZFV-EWR (Amtrak leg) with a notation “This is Not a Boarding Pass”

As an aside, I called UA about three or four days prior to OLCI to see if I could get an Amtrak reservation code. I could not get that reservation code and UA said contact Amtrak directly. Called Amtrak and their reservation agent did not have a clue. I just concluded that this was probably a very niche thing that only ZFV and EWR agents know. I didn’t want to get ping-ponged between UA and Amtrak.

Anyway, before my flight from EWR, I trek to Union Station in DC (Amtrak code WAS) and go to the ticket counter to see if I can get the ZFV-EWR Amtrak ticket. I show the ticket agent my UA boarding pass, including page 2 of the PDF with the “This is Not a Boarding Pass” notation along with my ID. After punching a few keys, the Washington Union Station ticket agent was able to give me my Amtrak ticket for the ZFV-EWR leg!

A couple things to note:

1. The reservation code for the Amtrak leg seems to be created a few days before your actual date of departure. I know this because I bought a DC-Philly Amtrak ticket separately and when I printed that paper ticket, it showed the date the reservation was made as well as that ticket’s reservation code. The date on the ZFV-EWR was two days before departure so I think that reservation was created a few days before departure and NOT when I booked my UA flight. See pictures for more details!
2. When I got my Amtrak reservation code, I could not add the ZFV-EWR ticket to my Amtrak app. Strangely, I was able to enter that same reservation at the Amtrak QuikTrak machine and it could pull up the reservation and spit out another paper ticket.
3. It helps to know your ZFV-EWR Amtrak train number. If you go to Amtrak.com, you can pull up all the schedules along the Northeast Corridor. So, UA 2854 won’t mean much to Amtrak ticket agents but UA 2854’s departure from ZFV at 8:30am means that is Amtrak train 130 with service from DC to New York Penn, and all intermediate stops. If I had my ZFV-EWR reservation code earlier, I could have booked a DC-Philly trip on train 130 separately instead of getting an earlier DC-Philly train than Amtrak train 130. That way, one needn’t exit at PHL; it would be one continuous trip!
4. If you somehow find your schedule doesn’t quite match the train timetables (i.e.: you booked your ZFV-EWR-XXX trip wayyyyy in advance), it could be that there was a schedule change on Amtrak. You should keep schedule changes in mind if you’re attempting to coordinate an uninterrupted train ride before ZFV like I should have done for train 130. As a tip, when you book your ZFV trip on UA, pull up the Amtrak schedule when you book for your date of departure and save it to your hard drive. I think Amtrak provides the schedules one year out so if there is a schedule change on your ZFV leg, maybe you can request a schedule change to your overall UA reservation, if you need it, and show the original PDF of the schedule change. Not sure UA keeps schedule changed of their partners, especially partners that use completely different systems.

United “flight” ZFV-EWR

Regular Amtrak ticket WAS-PHL (Amtrak codes)