Tickets can be bought online, in the stations or from approximately 4,000 travel agencies including those outside Italy.
It is common for people to buy tickets from the official website after looking up schedules.

Since long-distance trains, unlike the regional trains, usually require a reservation, it is advantageous to buy tickets in advance.

This also gives buyers access to a variety of discount schemes offered by Trenitalia.
All "premium" long-distance trains generally share the same discount schemes, even though their fares may differ.
Unlike mini fares, which existed before 2012 and required two days of notice, all tickets may be purchased at the last minute if they are still available.
All large rail stations have manned ticket windows and self-service ticket machines for this purpose.
Such machines, which either say "Trenitalia" or "Rete Regionale" ("regional network"), differ in the types of payment accepted.

The three fare classes that Trenitalia introduced in 2012 were "Base", "Economy" and "Super Economy".
A Trenitalia press release described the new fares as "Supereconomy, Economy, and Base, with the first two offering different levels of discount with respect to the Base fare.
The Base fare guarantees free and unlimited reservation changes up until train departure, while its price in second class and in the Standard level will be cut 5% on all the Frecciarossa and Frecciargento routes running on the High-Speed Torino - Salerno line."
Tickets can be bought online, in the stations or from approximately 4,000 travel agencies including those outside Italy. It is common for people to buy tickets from the official website after looking up schedules.
Since long-distance trains, unlike the regional trains, usually require a reservation, it is advantageous to buy tickets in advance.
This also gives buyers access to a variety of discount schemes offered by Trenitalia. All "premium" long-distance trains generally share the same discount schemes, even though their fares may differ. Unlike mini fares, which existed before 2012 and required two days of notice, all tickets may be purchased at the last minute if they are still available. All large rail stations have manned ticket windows and self-service ticket machines for this purpose. Such machines, which either say "Trenitalia" or "Rete Regionale" ("regional network"), differ in the types of payment accepted.
The three fare classes that Trenitalia introduced in 2012 were "Base", "Economy" and "Super Economy". A Trenitalia press release described the new fares as "Supereconomy, Economy, and Base, with the first two offering different levels of discount with respect to the Base fare. The Base fare guarantees free and unlimited reservation changes up until train departure, while its price in second class and in the Standard level will be cut 5% on all the Frecciarossa and Frecciargento routes running on the High-Speed Torino - Salerno line."
Trenitalia