Rome train from FCO to Termini

Unless something has changed since I was there in 2022, you don't need to buy tickets in advance. Just wait until you arrive to buy your ticket at the station (from the ticket office or a machine), then hop on the next train.

The Leonardo Express runs every 15 min
No need to purchase in advance

It’s a regional train-no reserved seats and price never changes
If train is full you stand or wait for next

I suggest that you download the Trenitalia app. That way, when you are through immigration and have walked to the train terminal (located conveniently at the airport) you can purchase your tickets on the fly. And you don't have to stand in line to get your ticket from a machine. Super easy!

Barbara's suggestion is a good one. You can also buy tickets at the snack bar near the machines.

Great suggestions! You have been very helpful, I appreciate it!

As noted this is a dedicated shuttle that only runs between two points. It is not like regular long distance trains. Not an ideal comparison, but like the subway train for the Chicago or Cleveland airports.

Is your hotel walking distance from Termini?

If not, by the time you pay for two train tickets and then a taxi, or other means of transport to the hotel, you will have spent very close to what the flat rate taxi fee from the airport to the hotel doorstep would cost..

Good point, I should have mentioned that our hotel is just a few blocks from Termini train station, so we can easily walk. Thanks for your advice

Tickets for the Leonardo Express from FCO to Termini are 14 euros each. A taxi from the airport to your hotel will be 50-60 (I don't think they have a flat rate anymore, but someone here will chime in if I'm wrong). When we took the Leonardo in December, it was a very long walk to the train, a very long wait for the elevator, and the train was standing room only, hot, and miserable. We could not move our feet because of all the people and luggage in the aisles and entry/exits.
Once you get to Termini, you have to walk to your hotel. You say it's close, but will you feel that way after a long flight from the U.S. and with your luggage in tow?
I will gladly pay the extra 20-30 euros in the future to take a taxi directly to my accommodations. Your hotel will likely even arrange a pickup for you so there won't be any surprises as to cost (which can happen in Italy, even when you're not sleep deprived).

I don't think I've ever taken a taxi from a European airport; public transportation has always been perfectly fine or me, even though I am zombified on arrival day. However, I want to warn you that there are some pretty broken-up sidewalks not far from Termini Station--not at all an uncommon situation in Rome, I found. On my latest trip to the city (Feb-Mar 2023), I stayed in Monti, and I didn't enjoy wrestling my bag along the 15-minute walk to my hotel (the Canova). I think I walked along Via Cavour.

We were just there last month and took a taxi from FCO to our hotel near Piazza Navona. There was a fixed price, I’m thinking 55 euros but I don’t recall for sure. But even if we rode the train we’d still need some kind of transit from the station so for 3 people the taxi made sense.

The flat rate to Rome city center is €55.00. Here’s the info from the FCO airport website:
https://www.adr.it/web/aeroporti-di-roma-en/pax-fco-taxi

I prefer to take a taxi directly to my hotel, but you should be fine since you’re close to Termini. If it’s raining though, I would take the taxi.

Thank you everyone for the very helpful information about taxis from FCO to City center!