Trains in Italy are generally good value; frequent, but of mixed reliability.

The railway market in Italy has been opened to competition, so on some high speed routes you have the choice between "Nuovo Trasporto Viaggiatori" or "Italo" (privately owned) and "Trenitalia" (state owned). On every other route, the state is the sole player, with either Trenitalia or a regional operator monopolizing local markets.

• Nuovo Trasporto Viaggiatori, ☏ +39 060708. NTV's "Italo" train service on Italy's high speed rail network serve Rome, Milan, Turin, Venice, Florence, Naples and other major cities. While they are not positioning themselves as a low-cost carrier (focusing instead on providing a more luxurious service), for some routes and dates their prices may be substantially lower than the competition. Check their website along with Trenitalia's to choose the cheapest or most convenient solution. Italian people generally refer to NTV as Italo. 

• Trenitalia, ☏ +39 892021. Trenitalia runs a wide range of train types: high-speed trains (Frecciarossa, Frecciargento, Frecciabianca), Intercity, regional trains (Regionali, Regionali Veloci) and international trains (Eurocity, Euronight).
  High-speed trains are efficient and very comfortable, travelling up to 360 km/h and stopping only at major stations. They connect Rome with Turin, Milan, Venice, Bologna, Florence, Naples and other cities. They are also the most expensive train type by far. To travel on these trains you are required to pay a supplement to the standard ticket, which includes the booking fee.
  Regional trains are the slowest, cheapest and less reliable, stopping at all stations.
  Intercity trains are somewhere in between high-speed and local trains. They are generally reliable, but if you need to catch a flight, for example, it might be better to pay extra for the high-speed trains. (updated Sep 2016)

On the train schedules displayed at each station, every train is listed in different colours (i.e. blue, red, green). The arrival times are listed in parentheses next to the names of each destination. One thing to watch out for is that certain trains only operate seasonally, or for certain time periods (for example, during holidays).

On long distance trains there are 1st and 2nd classes. A 2nd class ticket costs about 80% the price of a 1st class ticket. On high-speed trains you can also choose between basic, standard and flexible tickets. Basic tickets are of course the cheapest.

On high-speed trains seating reservation is compulsory. This means your seat is theoretically guaranteed, but it also means you will need to purchase tickets in advance. Many passengers with tickets for other trains that take a wrong one will have to pay the cheap fine for not having a seat reservation. As a result, on major routes or peak hours, expect to find your seat taken, in this case just showing the ticket is enough to get your seat.

During commuter hours, on major north-south routes during the holidays, or before and after large political demonstrations, trains on the lower train types can become extremely full, to the point where it gets very uncomfortable, in which case you could find yourself sitting on a tiny fold out flap in the hallway, where you'll have to move for everyone passing by.

While between Milan and Naples (including Bologna, Florence and Rome) high-speed trains cut travel times in half, on other routes, such as between Rome and Genoa, Naples and Reggio Calabria, Venice and Trieste, high-speed trains travel on the traditional line rather than on a dedicated high-speed line, with only marginally shorter travel times compared to Intercity trains, thus taking them might be a waste of money. Just check the Trenitalia website or the printed schedule, usually near the entrance to each platform, to see how long the trip will take.

On long routes, such as Milan - Rome or Milan - Reggio di Calabria, Trenitalia operates special night trains: Intercity notte. They depart around 22:00 and arrive in the morning. Depending on the train, you may be able to choose between normal seats, couchette and sleeper cabins of different categories. Seats are cheapest, but even sleeper cabins are not prohibitively expensive and are a very relaxing way to travel long distances. Some trains do not provide air conditioning so bring your own water bottle during the hot summer months.

The lines to buy tickets can be very long, and slow, so get to the station early. There are touch-screen ticket machines which are very useful, efficient, and multilingual, but there are never that many, and the lines for those can be very long too.

You can also buy tickets online on the Trenitalia website; you will receive a code (codice di prenotatione (PNR)) that is used to pick up the ticket from a ticket machine in the station ("Self Service"). For some trains you can also choose a ticketless option, where you print out the ticket yourself. See also below at Trenitalia Ticketless. You can also choose an option to have a "proper" receipt printed on the train, should you need one. By default the site will only show the "best" (usually more expensive) connections - you may select to "show all connections" to see if there are slower but cheaper connections available.

High-speed trains can fill up, so if you're on a tight schedule you should buy those tickets in advance. In general, you should buy the tickets before boarding the train. The Italian Rail has introduced heftier fines (starting at €50). If you're really running late and you have no ticket, it's probably best to directly talk with the conductor (il controllore or il capotreno) outside the train when boarding.

Remember that you must validate the ticket before boarding most trains, by stamping it in one of the white boxes (marked Convalida). Travelling with an unstamped ticket is treated the same as travelling without ticket. Don't forget to validate your ticket as the conductors are generally not tolerant in this particular matter. The exception are tickets which specify the day and time of travel; since those are only valid for one specific train they generally do not need to be validated.

The cheapest way to travel in a region is to buy a zone ticket card. A chart displayed near the validating machine tells you how many zones you must pay between stations. To buy a zone card for the next region you would have to get off the train at the last station and because the stops are so short you would have to board the next train (usually in about 1 hour).

A smoking ban in public places is in effect in Italy. You will be subject to fines for smoking on any Italian train.

There are special deals offered too, some of them are reserved to foreign tourist and others are available to locals. Some deals are passes that allow travel during a chosen period, while other special offers are normal tickets sold at decent prices with some restrictions. Before you choose to buy a pass, check first if it is cheaper than buying a normal ticket (or better, a discounted normal ticket, if available).

Italo regularly offers discount codes available if you buy a few weeks in advance on their websites, this is by far the cheapest option if you have a fixed plan. Trenitalia also has a Super Economy fare which sells out quite early. Both carriers have youth discounts.

If you are travelling a lot, and you're not Italian and a resident of another EU nation, you can get a Trenitalia Pass: you buy a number of days of travel to be used within 2 months, however you still have to pay a supplement on the compulsory reservation services, i.e. TBiz, Eurostar Italia, and Intercity which will be €5-25, depending on the train type. Details are on the website, and also on the RailChoice website ^{[formerly dead link]} .

Trenitalia's Ticketless option is only available when booked online or at an approved travel agency, and only for high-speed and intercity trains. The Ticketless solution allows you to buy a ticket online, get a PNR code via mail and board the train directly. You can choose whether to obtain a receipt by email or pick it up on board the train. On board you must tell the conductor your PNR code to allow him/her to issue the receipt, or confirm your presence on board if you have already obtained the payment receipt by email.