Updated June 2020
I live in the US but travel to Italy 3 to 4 times per year; here are my suggestions on how to use a US mobile phone in Italy:
Short stays (0 to 4 weeks)
I switched to Tmobile as a carrier 5 years ago when they started offering very good deals for overseas travelers.
Tmobile offers free text messages, free email, and free 2G connection ( very sloowww) for web browsing and other applications for travelers to 210 countries, including Italy. I personally use an iPhone (but any smart phone will do) since it switches to wifi calling, rerouting all calls to the internet when wifi is available.
On an Iphone go to Settings > Phone > Wi-Fi Calling
If wifi is available, then I can make and receive phone calls for free using my US phone number, just like I do when I am in the States ( double check this since rules change quickly). If wifi is not available, Tmobile charges 20 cents a minute (check latest fees) to use the cellular network. That is not much of a charge, but if you call often, you can install an application like WhatsApp.
According to T-mobile “When you travel abroad in 210+ countries and destinations you will have unlimited data at up to 128 kbps, which is great for web browsing, email, social media, and occasional use of certain features like GPS/maps”
The free 2G speed (128kbs) that Tmobile offers is enough to use WhatsApp for free and call the US using the App, so my phone calls costs are not significant anymore when I travel. Also the 2G speed is good enough to use Waze, Google maps or any other phone navigator.
In 2017 T-mobile added a new service, T-mobile One Plus. If you travel frequently internationally and require a higher internet speed you can add T-Mobile One Plus™ and get up to 256kbps speed abroad for $10/mo.
I personally set up my Whatsapp so I can use it to receive and make calls with all my contacts. The 256kbps internet speed provided by the cell network is ok to use the app from anywhere in Italy for free, without direct access to a wifi network.
Note that 256Kb is not enought to enjoy Netflix Hulu or Youtube ( for that you will have to activate an higher speed at your provider or use a local wifi).
If you use another carrier, you should check your carrier’s deals.
Use of a cell phone in Italy
Long stays ( 4+ weeks)
If you wish to stay in Italy for a long time, the best solution is to buy a local SIM card. Italian carriers like Tim, WindTre and Iliad offer a card; the problem is that, when you purchase one, they ask for a document and an Italian “codice fiscale” (sort of a Social Security Number). I have an Iliad and the cost is just 8 Euros a month or so. Since I have an Italian Codice Fiscale it was no problem for me to get the card, but when you don’t have one, you may need to ask an Italian friend to buy the SIM for you.
By Paolo Nascimbeni