Delivery Point Validation (DPV) indicates if an address is complete and correct. While the CASS process simply assigns ZIP + 4 codes based on a range of addresses, DPV checks to see if the specific address is valid.  It will detect incomplete addresses such as missing apartment numbers as well as flagging Commercial Mail Receiving Agencies.

DPV confirms that the specific address exists and the United States Post Office (USPS) is currently delivering to it. For example, we have a record with the address 123 Main Street. Standard Address
Correction will accept this address, as it falls within the valid range of Main Street addresses which is 100-200 Main Street. Any Main St. address with a primary number between 100 and 200 will be considered correct and receive a ZIP + 4 Code. However, there may only be houses at 121 and 125 Main St., so 123 Main St. does not physically exist and no mail can be delivered there.

The DPV requirement applies only to primary address information.

Key Advantages include:

  • Validating addresses before mailing reduces initial shipping costs
  • Reducing the number of returns due to incomplete or inaccurate information saves address correction and return fees
  • DPV extends the efficacy of CASS certification, which verifies the validity of ZIP codes, improving address quality and increasing delivery rates

How DPV Affects Postage

Because DPV processing is required for Address Correction, the number of mail pieces sorted into Automation and Carrier Route rates may drop, depending on the quality of your list. This is because these rates require valid ZIP + 4 Codes. Now that ZIP + 4 Codes will only be assigned if the primary number of an address passes DPV, some of your addresses may not receive a ZIP + 4 Code.

Ultimately, this is a good thing for both you and the USPS. You can identify which addresses are undeliverable and try to fix them, thereby ensuring that they will reach their intended destination. Without DPV, you could be receiving discounts on mail pieces, but they never reach anyone. The USPS benefits by only giving discounts to mail pieces that genuinely make their job easier and reduce the volume of undeliverable mail.


The initial drop in ZIP + 4 Code assignments will vary depending on your mailing list, but this drop should not be substantial if you are using a high-quality list.