Columbus OH 43215-2204 · DPV Y
Address verification · Proof
USPS CASS address verification for direct mail
Every address is checked against USPS CASS before it can mail. Proof holds anything it can't stand behind and tells you why.
Proof · checking with USPSUSPS CASS check231 / 247 mailable
1187 Foundry Row, Ste 210
Deliverable2210 Market St, Fl 3
Suite addedDenver CO · floor recovered
400 Canal Park Dr
Needs suiteBuilding has suites
14 Elm Ct
Won't mailUSPS reports vacant
88 Pine St, Ste 1400
DeliverablePortland OR 97204-3316 · DPV Y
If it won't deliver, it won't mail.
Found, uploaded or typed in, each address gets four USPS checks before it prints.
01
Standardized
Put into USPS format, with the ZIP+4 added.
02
Delivery point confirmed
DPV confirms USPS delivers to that exact address.
03
Suite checked
A missing or unconfirmed suite is held.
04
Vacancy flagged
An address USPS reports as vacant is held.
Held with a reason.
Each hold says what's wrong and what you can do. You decide.
| Reason | What it means | What you can do |
|---|---|---|
| Missing suite | The building has suites and the address names none. | Run suite repair or type the suite in. |
| Unconfirmed suite | USPS confirms the building but not the suite. | Correct the suite or run suite repair. |
| Vacant | USPS reports the address as vacant. | Pick another address or use headquarters. |
| Can't confirm | The address doesn't match a USPS delivery point. | Edit it or pick another. |
| Employer mismatch | The address belongs to a different company than the contact's employer. | Check the sources, then accept it or pick another. |
| Not found | Research found no business address it can stand behind. | Add an address you know or retry research. |
| Suppressed | The person matches your suppression list. | Nothing. They're left out automatically. |
You can also leave any held person out. An address you edit or type goes back through the USPS check.
Suite repair
Find the missing suite.
Suite repair goes back to research for held addresses and looks for the missing suite or floor number.
- The repaired address is checked with USPS again
- Anything still unconfirmed stays held
Suite repair
Before
400 Canal Park Dr
Cleveland OH · building has suites
Needs suiteAfter
400 Canal Park Dr, Ste 300
Cleveland OH 44113 · DPV Y
DeliverableHome offices
A published business address mails, even if USPS calls it residential.
Mailyard never looks up where a person lives.
Already have addresses?
Skip research and use no credits.
Uploaded and typed-in addresses go straight to the USPS check.
See pricing →Suppression list
Some people should never get a letter.
Add customers, competitors and anyone who asked you to stop, and they're left out of every drop.
- Emails, domains, LinkedIn profiles or company names, pasted or from a CSV
- A domain also matches its subdomains and the lead's company website
Suppression listUpload CSV
harborinsure.exampleDomain
priya@northdental.exampleEmail
Cartwheel AnalyticsCompany
linkedin.com/in/erik-lLinkedIn
Matched: marcus@east.harborinsure.example, through the domain entry. Left out of this drop.
Meet Proof · Verify
Postage is cheap. Wasted postage isn't.
Proof holds what won't deliver and applies your suppression list. You decide each hold.
Questions about verification
More in the full FAQ →
What does USPS CASS verification check?
CASS puts an address in USPS format and matches it against USPS data. Its delivery point check (DPV) confirms USPS delivers to that exact address, suite included, and flags vacant ones.
Can I verify a list that already has mailing addresses?
Yes. Uploaded addresses skip research, go straight to the USPS check and use no research credits.
Will Mailyard mail to an address USPS marks as residential?
Yes, when it's a business's own published address, such as a small business's home office.
Related
USPS CASS verification, explained
What CASS and DPV mean, what the codes tell you, and why suite numbers and vacancy flags decide whether a letter arrives.
GlossaryPlain definitions of direct mail and address-verification terms: CASS, DPV, RDI, NCOA, ZIP+4, First-Class and more.
Finding verified mailing addressesTurn emails and LinkedIn profiles into verified business mailing addresses, with the sources behind each one. Pay only for mailable results.
Event follow-upTurn a booth-scan list into letters that land on desks the week after the event, with a QR code back to your follow-up page.
Your next touchpoint fits in an envelope.
Upload a list and see how many addresses we can verify before you spend anything on postage.