Your mobile phone may or may not work in the BVI. If you are on the south side of Tortola, you may be able to connect to Cingular and Sprint, but other islands are problematic. The BVI have local companies only. Even if your U.S. mainland company assures you that your phone will work, don't count on it.
The area code for the BVI is 284; when you make calls from North America, you need only dial the area code and the number. From the United Kingdom you must dial 001 and then the area code and the number. From Australia and New Zealand you must dial 0011 followed by 1, the area code, and the number.
To call anywhere in the BVI once you've arrived, dial all seven digits. A local call from a pay phone costs 25¢, but such phones are sometimes on the blink. An alternative is a Caribbean phone card, available in $5, $10, and $20 denominations. They're sold at most major hotels and many stores and can be used to call within the BVI, as well as all over the Caribbean, and to access USADirect from special phone-card phones. For credit card or collect long-distance calls to the United States, use a phone-card telephone or look for special USADirect phones, which are linked directly to an AT&T operator. USADirect and pay phones can be found at most hotels and in towns.
USADirect (800/872-2881; 111 from a pay phone).