Simply enter the street address, city and state into the form on the USPS website. The search result provides the correct address with standard abbreviations and formatting, including a 9-digit ZIP code. The first 5 digits are all you usually need to include with your address.
If you are without Internet, a phone call to the local post office will provide you with the necessary code. Oftentimes, the ZIP codes for a local area are printed on the wall of that servicing post office or on the corresponding mail boxes outside the building.Learn more about United States