DAV checks a provided shipping address to confirm it's genuine and deliverable, using the same underlying systems the USPS itself relies on. It's especially useful for catching returned shipments before they happen, and for flagging bogus addresses on digital-goods orders where there's otherwise no shipping step to catch anything at all.
What it doesn't confirm
DAV verifies that an address exists and can receive mail — it says nothing about whether the person placing the order actually lives there. That distinction matters when deciding how much weight to give a DAV pass in a broader risk decision.
What to evaluate in a provider
- Coverage of the geographic regions you actually need
- How frequently the underlying address data is refreshed
- Recognition of PO boxes, private mailboxes, and suite numbers
- Address cleanup and standardization
- ZIP+4 appending and delivery point bar coding
- Residential vs. business address distinction
- Carrier route information
Implementation options
- Service bureau: pay per transaction through a third-party vendor
- In-house: license address database software and build your own API calls, or check manually via the USPS website
- Subscription: monthly or quarterly fees for ongoing software updates
Real-time verification at checkout is the recommended approach, since it lets the customer correct a bad address on the spot rather than after the order's already been placed.