Spend ten minutes researching virtual mailboxes and you will run into a four-letter acronym: CMRA. It sounds like bureaucracy, but it is actually the thing that makes the whole idea work. Understanding it makes the rest — the street address, the PMB number, Form 1583 — click into place.
Registered with the Post Office responsible for delivery as a Commercial Mail Receiving Agency.
Registration is a postal operating requirement, not USPS approval, certification, or endorsement. It does not by itself activate a customer address or establish that package service or every digital mail action is available. Those customer-facing capabilities require separate identity, Form 1583, facility, legal, security, and operational readiness checks.
What a CMRA is
CMRA stands for Commercial Mail Receiving Agency, the term USPS rules use for a commercial agent that receives mail for others. A provider may pair its physical receiving process with software for online review. Imaging, mail classes, timing, and actions vary by provider.
A street address with a PMB, not a box number
A CMRA may use a street-address format plus a private mailbox number. This example is illustrative and is not an EverAddress facility or customer address:
Jordan Rivera
1200 Harbor Street PMB 204
Austin, TX 78701
That "PMB 204" is your Private Mailbox designation. Because the address is a street address rather than a PO Box, some providers accept selected private-carrier items. Carrier acceptance, item limits, storage, and fees are provider-specific. Never send a package before confirming them.
How mail flows through a CMRA
- Supported mail arrives at the provider's receiving location using the approved PMB format.
- Staff match each piece to the right recipient and mailbox.
- The provider performs the check-in and imaging steps included in its actual service.
- The customer may request only actions the provider has enabled for that item and account.
- A trustworthy workflow records sensitive requests and staff completion.
You can see the workflow EverAddress is building on theHow it works page, and the privacy controls around the mailroom on theSecurity page.
The rules that protect you
Because a CMRA handles other people's mail, USPS sets requirements around it. The most visible one isForm 1583, which every recipient completes before the agency can receive their mail, along with identity verification. These rules exist to prevent fraud and to keep a clear record of who receives mail where.
A CMRA receives and handles mail. It is not a bank, aregistered agent, or a way to establish legal residency. Whether a given institution accepts a CMRA address for your specific purpose — a license, a registration, an account — is their decision and varies by jurisdiction. Always confirm before relying on it for anything beyond mail.
- CMRA is the USPS term for a commercial agent that receives mail for customers.
- A provider may assign a street-addressed PMB format rather than a PO Box.
- Package and private-carrier acceptance remain provider-specific.
- Form 1583 and identity checks are the rules that keep it accountable.
- Address acceptance for official purposes varies — confirm it yourself.
Common questions
Is a CMRA the same as a PO Box?
No. A PO Box is a box at a post office. A CMRA is a commercial mail-receiving agent that may assign a private mailbox (PMB) number. Package acceptance is provider- and carrier-specific; confirm supported carriers, item limits, storage, and fees before sending anything.
What is a PMB number?
PMB stands for Private Mailbox. It is the number that identifies your individual mailbox within the CMRA's street address, written like 'PMB 204'. USPS asks that CMRA addresses use the PMB designation so mail is routed to the right recipient.
Can I use a CMRA address for my driver's license or to register a business?
Sometimes, but not always. Whether a CMRA address is accepted for a license, vehicle registration, business filing, or banking is decided by that agency or institution, and the rules vary by state and organization. Confirm the specific requirement before relying on the address for anything beyond receiving mail.
Do all virtual mailboxes use a CMRA?
A U.S. business receiving mail for customers generally falls under CMRA rules. Provider software may add imaging and selected online actions, but those capabilities are not inherent to CMRA status and vary by service.
This guide is general information, not legal advice, and postal rules can change. Confirm current requirements with your provider and the relevant agency for your situation.