The Early Warning System (EWS) provides up-to-date address information for new and recently changed addresses that have not yet been updated in the monthly USPS database. EWS prevents address records from miscoding due to a delay in postal data reaching the USPS® databases.
The older the U.S. Postal Database, the higher potential you have for miscoding addresses. When a valid address is miscoded because the address it matches to in the U.S. Postal Database is inexact, it will result in a broken address.
EWS data consists of partial address information limited to the ZIP Code™, street name, predirectional, postdirectional, and a suffix. For an address record to be EWS-eligible, it must be an address not present on the most recent monthly production U.S. Postal Database.
The USPS® refreshes the EWS file on a weekly basis. You can download the EWS file from the USPS® website at https://postalpro.usps.com/cass/EWS. When you download the EWS database, you will receive a file named OUT. You must rename the OUT file to EWS.txt before using it.