Before you leave, check with your mobile operator to make sure your roaming service for internationals calls and for receiving your voicemail is activated. There may be a charge for this depending upon your operator. Try to use your phone for calling very sparingly as costs may be very high. If you planning to phone home several times whilst on holiday, we recommend purchasing an international phone card which you will find in many stores and result in very cheap calls to your friends and family at home.
To make phone calls to the United Kingdom from the United States, dial 011 44 followed by the number of the person you are calling without the 0 at the beginning of the number.
To call from one region to another, first dial 1 followed by the area code (for example 415 for San Francisco or 310 for Los Angeles). It is less expensive to call from public telephones than from your hotel room as the hotel charges more for calls. 800 numbers are toll free (from a public telephone).