When registering a .it domain with an Italian contact (country code IT), the registry will check the validity of the state / province used. The state / province must be stated as a 2-letter code according to the following table:
| Province | ISO code |
| Agrigento | AG |
| Alessandria | AL |
| Ancona | AN |
| Aosta | AO |
| Arezzo | AR |
| Ascoli Piceno | AP |
| Asti | AT |
| Avellino | AV |
| Bari | BA |
| Barletta-Andria-Trani | BT |
| Belluno | BL |
| Benevento | BN |
| Bergamo | BG |
| Biella | BI |
| Bologna | BO |
| Bolzano | BZ |
| Brescia | BS |
| Brindisi | BR |
| Cagliari | CA |
| Caltanissetta | CL |
| Campobasso | CB |
| Carbonia-Iglesias | CI |
| Caserta | CE |
| Catania | CT |
| Catanzaro | CZ |
| Chieti | CH |
| Como | CO |
| Cosenza | CS |
| Cremona | CR |
| Crotone | KR |
| Cuneo | CN |
| Enna | EN |
| Fermo | FM |
| Ferrara | FE |
| Florence | FI |
| Foggia | FG |
| Forlì-Cesena | FC |
| Frosinone | FR |
| Genoa | GE |
| Gorizia | GO |
| Grosseto | GR |
| Imperia | IM |
| Isernia | IS |
| La Spezia | SP |
| L'Aquila | AQ |
| Latina | LT |
| Lecce | LE |
| Lecco | LC |
| Livorno | LI |
| Lodi | LO |
| Lucca | LU |
| Macerata | MC |
| Mantua | MN |
| Massa and Carrara | MS |
| Matera | MT |
| Medio Campidano | VS |
| Messina | ME |
| Milan | MI |
| Modena | MO |
| Monza and Brianza | MB |
| Naples | NA |
| Novara | NO |
| Nuoro | NU |
| Ogliastra | OG |
| Olbia-Tempio | OT |
| Oristano | OR |
| Padua | PD |
| Palermo | PA |
| Parma | PR |
| Pavia | PV |
| Perugia | PG |
| Pesaro and Urbino | PU |
| Pescara | PE |
| Piacenza | PC |
| Pisa | PI |
| Pistoia | PT |
| Pordenone | PN |
| Potenza | PZ |
| Prato | PO |
| Ragusa | RG |
| Ravenna | RA |
| Reggio Calabria | RC |
| Reggio Emilia | RE |
| Rieti | RI |
| Rimini | RN |
| Rome | RM |
| Rovigo | RO |
| Salerno | SA |
| Sassari | SS |
| Savona | SV |
| Siena | SI |
| Sondrio | SO |
| Syracuse | SR |
| Taranto | TA |
| Teramo | TE |
| Terni | TR |
| Trapani | TP |
| Trento | TN |
| Treviso | TV |
| Trieste | TS |
| Turin | TO |
| Udine | UD |
| Varese | VA |
| Venice | VE |
| Verbano-Cusio-Ossola | VB |
| Vercelli | VC |
| Verona | VR |
| Vibo Valentia | VV |
| Vicenza | VI |
| Viterbo | VT |
