Understanding the Early Warning System (EWS)
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 data updates. EWS prevents address records from miscoding due to a delay in postal data reaching the USPS address matching files.
The older the U.S. Postal Databases, 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 records containing partial address information limited to the Zip Code, street name, pre-directional, post-directional, 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 Web site a https://postalpro.usps.com/cass/EWS .