Will my U.S. mobile phone work in Cuba?
Maybe. Some U.S. carriers have or are beginning to make agreements with ETECSA (the Cuban national telecommunications company) to provide roaming services in Cuba. Sprint and Verizon, for example, currently offer roaming services in Cuba. If your carrier offers a roaming plan and your mobile phone is capable of roaming in Cuba, you should ask your carrier about any additional charges for voice calls, data, and outgoing text messages that you may incur during your trip. The telecommunications market in Cuba is changing rapidly, so before you travel, be sure to check with your wireless provider for the latest developments.
Another way you can use your U.S. mobile phone in Cuba is to rent a SIM card. If you have an unlocked GSM-capable mobile phone, you can rent a SIM card from Cubacel (ETECSA’s mobile phone arm) that will allow you to use your mobile phone in Cuba. Cubatel’s SIM cards come with pre-paid minutes in amounts of 10, 20, or 40 Cuban convertible pesos (CUC$) (US$10, $20, or $40), plus a daily rental fee for the SIM card of CUC$3 (US$3). The per-minute call charges and texting fees for renting a mobile phone (as listed below) also apply to renting a SIM card. Contact your wireless provider to check whether your mobile phone operates on the compatible standard and request that your carrier unlock your mobile phone.
To read more visit https://www.fcc.gov/consumers/guides/telecommunications-faqs-travelers-cuba