Individuals sending out mail in the US have been advised to fill out addresses correctly to minimize the chance of returned mail.
According to an article by the Daily Breeze, because the United States Postal Service (USPS®) machinery scans the entire address data rather than just the ZIP Code, entering the data wrong can cause mail to be rejected.
A USPS spokesperson explained that USPS delivers mail using ZIP Code, city and state information.
They told the website that the third line of the address represented the city, state and ZIP code of the post office that delivered the mail to the address displayed in the second line of the mail.
If this was not correct or presented conflicting information it would be rejected.
The use of bad addresses in Intelligent Mail® barcodes has also been cited as a reason for returned mail.
A report on the Dead Tree Blog stated that returned mail with a barcode on it will be scanned again and if it contains a bad address, the likelihood is it will go back to the listed destination.