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DPV

Delivery Point Validation, or DPV, is a USPS address management product that tells whether a ZIP + 4 coded address is a known address record in USPS's delivery file. Users run it to confirm known USPS addresses and to find addressing problems that may hinder delivery.

Updated October 31, 202627 sources

What it is

DPV is a set of secure datasets, called hash tables, that hold representations of known addresses. USPS's address database holds over 165 million address records. DPV is for customers who have to confirm that a ZIP + 4 address is a USPS delivery point.

For each address, DPV confirms one of three results:

  • The known address has verifiable primary and secondary data.
  • The known address has verifiable primary data but not secondary data.
  • The address cannot be verified as a known address.

DPV only checks: it does not add missing data or correct any part of an address. It cannot assign a ZIP + 4 code, and it does not answer for an address without one. It returns nothing about the business, owners or residents at an address.

Correcting address problems can reduce undeliverable-as-addressed pieces and make mail processing and delivery more efficient.

End Users are customers who receive CASS Certified DPV data from a licensed service provider. Standalone Users receive specially packaged DPV data instead. Their packages allow limited lookups outside CASS operations and for non-mailing purposes.

How it works

A CASS Certified address-matching product matches and standardizes an address within a range of addresses. DPV goes one step further and validates the address as a known USPS address record.

One address, from the mailer's list to a DPV answer.

  1. CASS Certified software gives the address a 9-digit ZIP Code and parses it, right before validation.
  2. The interface queries DPV with the 9-digit ZIP + 4 code and the parsed address.
  3. Each negative answer from the A hash table triggers a query of the False Positive table.
  4. The software assigns a return code and every standard footnote code that applies.
  5. The output holds the original address as presented.
  6. It also holds the standardized address with its ZIP + 4 and delivery point code.

Return codes

DPV answers every query with one return code, a letter or a blank.

CodeMeaning
YThe primary number and any secondary number are confirmed.
DThe primary number is confirmed, and the secondary information is missing.
SThe primary number is confirmed, but the secondary information given is invalid, or a trailing letter was dropped to match.
NThe primary number failed to confirm.
BlankThe address was not presented to DPV.

An enhanced set of return codes adds R, for a confirmed address on a phantom route where USPS does not deliver.

Standard footnote codes travel with the return code and say more about the match. USPS set them so products are consistent and customer data is easier to evaluate. Customers get them on request.

Return codeFootnotesWhat it tells the mailer
YAA BBNo action needed: every part of the address is confirmed, and a ZIP + 4 code is returned.
SAA CCVerify the secondary information, which DPV cannot confirm; a ZIP + 4 code is returned.
DAA N1Verify the missing secondary information; only the primary number is confirmed.
NAAVerify the address: the ZIP + 4 file matched, but DPV cannot confirm it, and no ZIP + 4 code is returned.

Data files

Beyond the main hash tables, the DPV product carries tables that flag particular kinds of address.

TableWhat it flags
CMRAA private business that acts as a mail-receiving agent for specific clients.
DropA delivery point that gets mail in one receptacle or drop site serving several dwellings or businesses.
False PositiveThe addresses that trigger false positive reporting.
No-StatAn address that does not receive delivery and is not counted as a possible delivery.
VacantA delivery point that was active, is now vacant, in most cases for over 90 days, and does not receive delivery.
PBSAA Post Office Box Street Address.
Door Not AccessibleAn address where carriers cannot knock on the door or reach the building, such as a long driveway or gated community.
NSLAn address with no secure location.
ThrowbackA street address whose mail goes to the customer's PO Box.
Non-Delivery DaysWhether, and on which days, mail is not delivered to the address.
No-Stat Reason CodeWhy a record is flagged as a No-Stat.

Updates

USPS provides DPV updates each month through Electronic Product Fulfillment. Only the two most recent releases are available to download. Licensees must update the DPV tables with the matching release of the ZIP + 4 file. USPS recommends a monthly ZIP + 4 release for the best DPV results.

Licensing and testing

Only CASS software makers can license DPV: an applicant must be one, or be becoming one. Licensees must hold CASS certification for ZIP + 4 coding before DPV licensing. The annual license fee is $22,800.00. The first license year is prorated.

How a software maker becomes a DPV licensee.

  1. Complete the certification process and its documents.
  2. Execute the license and pay the licensing fees.
  3. Have USPS review, test and approve the interface before any production processing.
  4. Receive USPS's written approval or rejection of the interface.

USPS tests each licensee's system with known and unknown delivery points. The test also checks false positive reporting and the stop. It runs each year with CASS certification, and whenever a ZIP + 4 or DPV software part changes significantly. For each test address its CASS process codes correctly, an applicant must give every DPV element with 100 percent accuracy.

Test data for Stage I and II testing never expires, and its data date is eight 9s. It is for testing only and cannot be used in production. Licensees must not export the DPV product outside the United States or its territories.

Rules

A Licensee or software developer writing an interface to the DPV product must first ensure the address list is processed through USPS CASS Certified software to obtain a 9-digit ZIP Code™ and a parsed address immediately prior to the validation process.

An address list must go through CASS Certified software right before DPV. That run gives each address its 9-digit ZIP Code and splits it into parts.

Per the License Agreement, the DPV product shall not be used to facilitate the creation of address lists artificially.

DPV must not be used to help make address lists artificially. The False Positive table is there to catch it.

For each negative response that occurs in a query of the A hash table (dph.hsa), a query must be made to the False Positive table.

Every time the A hash table answers no, the software must also query the False Positive table.

Any time an address encounters a match to the False Positive table, the interface must cease validating delivery points of addresses for the specific address list.

The interface must stop validating an address list as soon as one of its addresses matches the False Positive table.

Licensees will design a process that will cause the DPV interface to stop working when the DPV data has aged more than 105 days from the product date.

A licensee's DPV interface stops working once its data is more than 105 days past the product date. The licensee builds this cutoff into the interface.

Where DPV licensed materials are used in an online format, the information returned to the inquiring system shall be limited to confirmation of whether the input is a known address record.

An online DPV lookup must return only whether the address is a known address record.

Whenever there is a 49 percent or greater difference between ZIP + 4 file matches and DPV confirmed addresses in a processed mail list, the occurrence must be reported to Dsf2stop@usps.gov (see Calculating Percentages for the DPV False Positive Header Record -- Exhibit A).

When ZIP + 4 matches and DPV confirmations in a list differ by 49 percent or more, the case must be reported to Dsf2stop@usps.gov.

USPS-supplied DPV updates more than 60 days old shall be destroyed using common practices for disposal of sensitive materials, such as permanent file deletion.

DPV updates more than 60 days old must be destroyed, for example by deleting the files for good.

What goes wrong

The False Positive table holds artificially made addresses, to catch lists that were not legitimately obtained. For an End User, a match halts validation of that address list at once.

What follows when an End User's list matches the False Positive table.

  1. Validation stops for that list, and other address lists may continue.
  2. The End User may still standardize the rest of the list's addresses.
  3. The End User notifies the Licensee that processing was halted.
  4. The Licensee reports the customer's name and address to USPS in the Exhibit A layout.
  5. The Licensee sends the affected addresses to Dsf2stop@usps.gov, subject line DPV False Positive.
  6. A one-time restart code restores processing.

The restart code works once and cannot bypass a later stop. USPS can require a Licensee to suspend an End User after multiple incidents of artificial address detection. Documentation given to End Users must carry USPS's explanation of the stop. It starts: "During the processing of your list, an artificially created address was detected."

Licensed NCOALink Full Service Providers may continue, but must notify USPS immediately. MASS processing on MLOCR equipment may also continue, and its provider can send the file by email or by fax to 650-577-2500. In a call center, USPS will consider a false positive report in place of the stop.

A low match rate is reported, but processing does not stop. The match rate is the records DPV matched divided by the potential ZIP + 4 records, times 100. In USPS's example, 656,679 DPV matches out of 703,156 potential records give 93.39%.

An address DPV does not match gets a standardized address with a 5-digit ZIP Code, as appropriate. When no standardized address is possible, the address goes back as it was presented.

When USPS finds a problem in a licensee's DPV process, it can direct a fix, or suspend or end the license.

Terms

Coding Accuracy Support SystemCASS, CASS software program, CASS certification process, Coding Accuracy Support System (CASS) certification
provides hardware and software manufacturing, service bureaus, and commercial mailers a common measure by which to test the quality of address-matching software.
ZIP+4ZIP+4 CODE
An enhancement to the 5-digit ZIP Code that uses an additional four digits to represent the sector (a geographic area or neighborhood) and segment (a smaller unit such as a building, floor, street block) for an address within a 5-digit zone.
delivery pointDP
(1) A single mailbox or other place to which mail is delivered. A street address does not necessarily represent a single delivery point because a street address such as one for an apartment building may have several delivery points. (2) A specific set of digits between 00 and 99 assigned to every address that is combined with the ZIP+4 code to provide a unique identifier for every delivery address. The DP is encoded within the POSTNET or Intelligent Mail barcode.
Undeliverable as AddressedUAA, UAA mail
mail that the USPS cannot deliver as addressed and must be forwarded to the addressee, returned to the sender, or discarded depending on the authorized treatment for that mail class and/or specific instructions provided by the mailer through ancillary service requests
False Positive table
To detect conditions where address records appear to be the result of artificial manufacture, and not legitimately obtained, a table of artificially-manufactured addresses is provided as part of the product.
End User
End Users are classified as customers receiving CASS Certified DPV data from a Licensed Service Provider.
Commercial Mail Receiving AgencyCMRA, commercial mail receiving agencies, Commercial Mail Receiving Agent
A private business that provides mail delivery service to individuals or business that rent Private Mail Boxes (PMB) through them.
vacant delivery point
A delivery point that was active in the past but is currently not occupied (generally not occupied for 90 days or more) and not receiving mail delivery. It does not include businesses or homes under construction, demolished, or otherwise identified as unlikely to become active.
no-stat delivery point
A business or dwelling under construction, demolished, blighted or otherwise identified as not likely to become active for some time, or a rural route address that has not been receiving mail for 90 days or longer. No-stat and vacant tables are part of the Delivery Point Validation product.
Electronic Product FulfillmentEPF, Electronic Product Fulfillment (EPF) web site, Electronic Fulfillment Website
A secure web-based application managed by the National Customer Support Center in Memphis TN that is used to post and receive Address Management and Address Information System products, including ACS fulfillment files.
Multi-Line Optical Character ReaderMLOCR
Equipment used by mail service providers that applies a barcode and presorts mail, enabling the mail owner to take advantage of automation discounts.

Documents

Tech Guides

User Guides

Fact Sheets

Quick Service Guides

Contact Lists

Data Files

Release Notes

Applications/Forms

Contacts

The Move Update Support Department answers questions about DPV and its licensing and certification at 1-800-589-5766. False positive files go to Dsf2stop@usps.gov.

Sources