No. Mobile phones on U.S. contracts don’t have roaming access because of restrictions relating to the U.S. economic embargo on Cuba. Some roaming coverage is available for accounts with certain foreign carriers, but charges are high.
Some visitors with compatible phones rent or buy a Cuban SIM card for local and international calls. Government-owned mobile carrier Cubacel sells temporary SIM cards to visitors, with locations at the airport and at several spots in the city. International and local calls under this arrangement will be very expensive, but we have found this is a useful way to be reachable by business/family contacts in the U.S. Incoming calls do not accrue charges when you are using a Cuban SIM card.