Address Validation
Enterprise Shipper (ES) can use one of four address validation methods. Each Provider has its address validation feature, or Window Book provides TrueAddress for validation. For domestic mail, TrueAddress provides deliverability scores. Just because an address is valid does not mean it is deliverable. You may want to give it a try, you will need to register, but there are no costs to use (located in Optional Settings > Address Validation Settings).
The EasyPost, International Bridge, and Pitney Bowes validation options are "Default Provider Validation Option".
Default Provider Validation Option
Address Validation - Validation Score/Status
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