---
title: "How to get verified mailing addresses for B2B prospects"
description: "Where B2B mailing addresses come from, how CASS, DPV, and NCOA verification works, and how to handle the office-vs-home problem."
canonical: https://trysincerely.com/guides/b2b-mailing-addresses
last_updated: 2026-09-13
---
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# How to get verified mailing addresses for B2B prospects

> Where B2B mailing addresses come from, how CASS, DPV, and NCOA verification works, and how to handle the office-vs-home problem.

Source: https://trysincerely.com/guides/b2b-mailing-addresses

You get verified B2B mailing addresses in three steps. First, pull candidate addresses from your CRM, a data vendor, or a business registry. Second, check addresses against the destination country's postal data. For US mail, inspect standardization and DPV results from CASS-certified processing, and check NCOA for filed moves. Canadian addresses need Canadian postal verification. Third, suppress anyone who should not get mail. Skip step two and a substantial share of a raw CRM list comes back undeliverable, though the exact rate depends entirely on how your list was built. Skip step three and you mail people who asked you to stop.

## Why your CRM addresses are worse than you think

CRM address fields rot. Sales reps paste whatever LinkedIn showed that day. Companies move offices and nobody updates the record. A field labeled "address" often holds a city, a headquarters from three years ago, or nothing. The email side of your CRM gets bounce feedback that cleans itself. The address side gets no feedback at all until a piece comes back marked return to sender, weeks after you paid for it.

Treat every CRM address as a claim, not a fact. Verify before you print.

## Where addresses come from

Three sources, in order of how much you should trust them:

1. **Your CRM.** Best when the address came from a signed contract, a shipped order, or a billing record. Worst when a rep typed it in during discovery. Check the field's provenance before trusting it.
2. **Data vendors.** ZoomInfo, Apollo, Clay enrichments, and similar tools sell company HQ addresses. These are usually right for the company and wrong for the person. A vendor gives you the headquarters; your prospect may sit in a satellite office or at home.
3. **Business registries.** State incorporation filings, Companies House in the UK, and Google Business Profiles list legal or storefront addresses. Free and authoritative for small businesses. For larger companies the registered agent's address is often a law office, not a mailbox anyone useful checks.

No single source wins. The practical move is to resolve an address per account from whichever source has the freshest evidence, then verify it.

## What verification actually checks

For US addresses, distinguish software certification, delivery-point results, and filed moves:

- **[CASS](https://trysincerely.com/glossary/cass)** certifies address-matching software. That software standardizes addresses and assigns postal codes; it can also flag missing information.
- **DPV** (Delivery Point Validation) confirms that exact mailbox exists on a carrier route. A standardized string alone is insufficient; check the DPV result. This is the pass that kills undeliverable mail.
- **[NCOA](https://trysincerely.com/glossary/ncoa)** checks the USPS change-of-address database, which holds up to four years of moves. It kills mail to the office a company left last spring.

A suite number matters more in B2B than anywhere else. "Suite 400" missing from a 40-story tower means the mailroom guesses, and mailrooms guess badly. DPV flags addresses that need a secondary number, so treat that flag as a hard stop, not a warning.

For a deeper walkthrough of these checks, read [address verification explained](https://trysincerely.com/guides/address-verification-explained).

## The office-vs-home problem

Since 2020 a verified office address no longer means your prospect is in that office. The building exists, DPV passes, and the piece still lands in a mailroom pile nobody sorts until Thursday, or never.

There is no clean database fix for this. What works in practice:

- Prefer accounts with evidence of a physical presence: shipping records, event badges scanned at their office, a storefront, job posts mentioning the location.
- Mail roles that anchor to the office: finance, operations, facilities, executives with assistants who open mail.
- For remote-heavy targets, consider whether mail is the right channel at all. A LinkedIn touch or a call may beat a piece rotting in a mail slot. Direct mail is not the answer to every account.
- Never look up home addresses for B2B outreach without explicit consent. It is invasive, it is a compliance risk in most privacy regimes, and it burns trust with the exact person you want to win.

## Suppression hygiene

A [suppression list](https://trysincerely.com/glossary/suppression-list) is the do-not-mail counterpart of an email unsubscribe list. Keep one, and make it global: opt-outs, current customers you should not prospect, competitors, dead accounts, and any address that came back undeliverable. Check every send against it, every time, across every campaign and every teammate. The [suppression operations guide](https://trysincerely.com/guides/direct-mail-suppression) explains how to keep later CRM syncs and CSV imports from reopening the door.

Sincerely includes address resolution and mailability review: addresses are resolved from CRM and public sources and checked for mailability before anything prints, verification is included on every plan, and suppression is immediate and global. US addresses use USPS delivery-point checks; Canadian addresses use Canada Post verification. These checks do not establish that a named contact still works there, and do not imply an NCOA check. If you run mail through your own stack, ask your provider which checks it performs and enforce suppression in code.

An unverified address is not a lead, it is a donation to your printer.

## Related questions

- [CASS, NCOA, and address verification, explained](https://trysincerely.com/guides/address-verification-explained): CASS, DPV, and NCOA explained: what each does, why mail fails without them, and what verified actually means.
- [How to manage direct mail suppression across campaigns](https://trysincerely.com/guides/direct-mail-suppression): Keep one durable do-not-mail decision per contact, check it at dispatch time, and cancel every queued piece that has not reached the print vendor.
- [What is provenance?](https://trysincerely.com/glossary/provenance): Provenance is the recorded origin of a data point, the source and date behind an address or account fact, so you can judge whether to trust it before you print.
- [What is the best direct mail targeting software for B2B?](https://trysincerely.com/guides/b2b-direct-mail-targeting-software): B2B mail targets accounts, people, and office addresses, not households. Which tools pick the account, the person, the address, and the week to send.

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Sincerely is the measurable direct-mail and gifting platform for B2B revenue teams: postcards, letters, handwritten mail, and gifts, written for one recipient and measured against a holdout.

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