Subject: Re: Italian train supplements
Flavio, your are not completely right: The surcharge is not due if you 1) notify the conductor upon boarding; 2) You have a ticket valid for a lower category of trains 3) You are traveling on a non regional trains (regional trains are not only Regionals but also D and iR trains)

So the suggestion in case of doupt on which train to get, is buying a 2nd class ticket for a iR train, then ask the conductor to integrate the fare. Note that if the integration is from 2nd to 1st class condition 3 is not required.

Leonardo Boselli Firenze, Toscana, Italia, Europa