Area code 473 is the local telephone area code of Grenada, Carriacou and Petite Martinique. The 473 area code, or "(GRE)" was created during a split from the original 809 area code which was completed in October 1997.
When in Grenada, Carriacou or Petite Martinique the seven digits are used alone. Calls to Grenada from anywhere in the United States or Canada are dialed 1(473) + seven digit phone number.
Area code 473 Wikipedia
The 473 area code has been linked to a form of telephone fraud known as the "one ring scam". The person perpetuating the scam calls the victim via a robodialer or similar means, sometimes at odd hours of the night, then hangs up when the phone is answered with the hope that the victim will be curious enough to call the number back. When the victim does this, an automatic $19.95 international call fee is charged to their account, as well as $9.00/min thereafter. Similar scams have been linked to Antigua (area code 268), Jamaica (area code 876), the Dominican Republic (area code 809) and the British Virgin Islands (area code 284).