Telephone numbers in Cuba

Telephone numbers in Cuba all have the same format, consisting of the country code (53), followed by an area code.

Phone numbers in Cuba have up to eight digits. The first one to two are the area code, the remaining digits are the subscriber number.

Calls between different area codes are prefixed with the trunk prefix 0, followed by the area code.

The international call prefix is harmonized to 00 (fix line formerly used 119 while mobile always used 00).

(https://it.granma.cu/cuba/2019-04-26/etecsa-installera-il-codice-daccesso-00)

The mobile numbers format is 5xxx xxxx.

List of area codes in Cuba
The Guantanamo Bay Naval Base, operated by the United States Navy, has an unofficial area code of 99, which is only dialable from within the United States. Dialing 011 53 99 returns a second dial tone, after which the local number at the naval base can be dialed.