I scheduled to arrive in Rome at 4:35pm, and am trying to determine what time I should purchase a train ticket to Rome Termini- I am not checking bags, I am wondering how long it will take to go through passport control (I connect through Amsterdam on the way and believe that is where I go through EU customs)?

Hi @Stacey L McCrath-Smith35 welcome to the community!

The Leonardo Express tickets are valid for 4 hours from the time you choose.

I have actually got through several times from my plane to the platform in as little as 20 mins (yes true!) but usually 30-35 mins. with no checked bags.

I would book a train that is 30 mins from your arrival time and it will be valid for 4 hrs after that in case you need more time :-)