US Business Address Types: Glossary and Uses

Why one company ends up with several addresses

When you set up a US company, the state, the IRS, the Postal Service, your bank and your customers all ask for an address. They are not asking the same question. The state wants to know where legal papers can be delivered. The IRS wants to know where to send letters. USPS wants to know who is allowed to receive mail at a mailbox. A bank wants to know where the business actually operates.

The Small Business Administration's registration guide lists business location and registered agent information among the details states typically ask for when you register (source). Many founders find that one address can't do every job, so they end up with two or three, each used in the right place. That's normal, as long as each one meets the rules of the form it's on.

The glossary: each address type in plain English

Each entry gives a plain definition, where you're typically asked for it, and the limits that commonly apply.

Registered agent address (registered office)

The street address of your company's registered agent in the state where the company is formed or registered. The agent receives official papers and legal documents for the company and must be located in that state (SBA).

• Where it's asked: your formation filing (articles of organization or incorporation) and later state filings. It's part of the public record.
• Common limits: it must be a physical location. Wyoming says post office boxes, drop boxes, virtual addresses, mail forwarding locations and UPS or FedEx stores don't qualify (source). Delaware says an agent can't do the job solely through a virtual office or a mail forwarding service (6 Del. C. § 18-104).

Principal office (principal place of business)

The main place the company does business from. Wyoming defines it as "the principal place of business for the Entity, regardless of location," and says it may be, but doesn't need to be, the registered office (Wyoming SOS rules, ch. 1).

• Where it's asked: some state formation forms and annual reports. Wyoming's LLC articles ask for it (source).
• Common limits: Wyoming allows it to be anywhere, in or outside the state. Where a state form asks for it, it is usually public.

Mailing address

Where the company receives its post. Wyoming's rules define it as "an address where mail is received," which "may be separate from the physical street address" and "may be a post office box" (source).

• Where it's asked: state forms, the IRS EIN application (lines 4a–4b of Form SS-4), banks, platforms and anyone who needs to send you letters.
• Common limits: fine for correspondence, but not accepted where a form specifically asks for a physical or street address.

Physical address (street address)

A real location with a street address, as opposed to a P.O. box. For a company it usually means where the business operates. The IRS asks for it on Form SS-4 only if it differs from the mailing address (source).

• Where it's asked: Form SS-4 lines 5a–5b, registered office fields, and bank or platform applications that check where you operate.
• Common limits: no P.O. box. Some providers also treat a mailbox or registered agent street address as not physical enough (see below).

Residential address

Your home. Founders often use it at the start, and it's a real physical address, but it has trade-offs.

• Where it's asked: personal identity checks by banks and platforms (for owners and account representatives), and USPS Form 1583, where the mailbox operator verifies the applicant's permanent address (USPS DMM 508).
• Common limits: if you put it on a state filing it can become public. Local zoning rules can still apply to home-based businesses (SBA). For non-US founders, a home address abroad is not a US address. Our privacy page covers keeping a home address off the record.

P.O. Box

A mailbox rented from the US Postal Service at a Post Office.

• Where it's asked: it can serve as a mailing address, for example on Wyoming filings (source).
• Common limits: not accepted as a registered office (source) or as the street address on Form SS-4 (source). At some Post Office locations, USPS offers a "Street Addressing" option that lets a P.O. Box use the Post Office's street address with the box number (USPS DMM 508).

CMRA (Commercial Mail Receiving Agency)

USPS defines a CMRA as "a private business that accepts mail from the Postal Service on behalf of their customers and delivers it to a private mailbox (PMB)" (source). Virtual mailbox services and many shipping stores operate as CMRAs.

• Where it's used: as a mailing address for letters, bank cards and statements, and as the address for a virtual mailbox.
• Common limits: you must complete PS Form 1583 and show two forms of ID, one with a photo. Registered Mail has to be collected at the local Post Office, and mail can be forwarded to a CMRA but not from one (source).

PMB (private mailbox)

Your mailbox number at a CMRA. USPS rules require the address to carry "PMB" or "#" with the number, and mail without it may be returned to the sender as "Undeliverable as Addressed, Missing PMB or # Sign" (USPS DMM 508).

Virtual address and virtual office

A virtual address is a street address you use without working there, usually run by a mailbox service. A virtual office adds some use of real space, such as a coworking address or meeting rooms at a member rate. Both are commonly used as a company's mailing or public address.

• Where it's used: websites, invoices, correspondence, and some state forms that allow any mailing address.
• Common limits: not a registered office in Wyoming (source) or Delaware (source). Some providers identify and reject mailbox or virtual addresses (Stripe). Our virtual mailbox vs virtual office comparison explains the practical differences.

Responsible party (Form SS-4)

Not an address at all, but often confused with one. The responsible party on an EIN application is the individual who controls the entity. The IRS asks for that person's name and taxpayer number (SSN, ITIN or EIN) on lines 7a–7b, and says it must be a natural person, not an entity (source). The addresses on the form belong to the company.

Which address goes where

This table sums up where each kind of address is typically asked for, and the rule behind it. Rules differ by state and by provider, so treat it as a starting point and check the specific form.

Addresses on the IRS EIN application (Form SS-4)

The EIN application is where many founders first meet the difference between a mailing address and a street address. The IRS instructions are short and specific (source):

In practice, the mailing address is the one that matters most, because it's where the IRS sends its correspondence. If you use a mailbox service for mail, make sure it can receive and scan IRS letters.

If the address changes later, the IRS says to file Form 8822-B to report a new business mailing address or business location. The same form reports a change of responsible party, which must be reported within 60 days (source).

Registate prepares EIN applications as a paid service; the EIN itself is free from the IRS. See EIN application support and our guide on applying for an EIN without an SSN.

CMRA, PMB and Form 1583: the mailbox terms

If you use a virtual mailbox, your address is a PMB at a CMRA. That's a legitimate, USPS-regulated way to receive mail, with a few rules attached (USPS, DMM 508):

1. 1
   Form 1583 for each recipientEvery person or business receiving mail at the PMB completes PS Form 1583, which authorizes the CMRA to receive their mail.
2. 2
   Two forms of IDOne must have a photo. The CMRA also verifies the applicant's permanent address.
3. 3
   PMB or # on every addressWrite the address with the PMB or # designation, exactly as the CMRA gives it, so mail isn't returned.
4. 4
   Know what a CMRA can't doRegistered Mail is collected at the Post Office, and USPS doesn't forward mail onward from a CMRA.

Registate's virtual mailbox works this way: a real US street address with a PMB, Form 1583 completed online, and mail you can scan, forward or store.

How banks and payment platforms treat address types

Banks, fintechs and payment platforms aren't bound by the state's or the IRS's address rules. They set their own, and they decide each application themselves. Many ask for the company's address and each owner's or representative's personal address, and some check what kind of address it is.

Stripe is one provider that documents this in detail. For its Issuing, Treasury for platforms, Opal and Corporate Card products, Stripe says it checks that addresses are not P.O. boxes, private mailboxes, CMRA addresses or registered agent addresses, for both the business and the account representative (source). A flagged registered agent address can be appealed with proof such as a lease or a utility bill for that address.

• A registered agent address is commonly refused as a company's operating address.
• Mailbox and virtual addresses are commonly flagged by providers that require a physical presence.
• Documents in the company's name for the same address, such as a lease or utility bill, are commonly what providers ask for as proof.

Rules differ, so read each provider's own page. We summarize published requirements for Mercury, Stripe and Amazon seller verification, and why banks say no covers common reasons for a decline. Registate's lease-backed address comes with a commercial lease and a utility bill, but each provider still makes its own decision.

Keeping your addresses consistent

Having several addresses is fine. Having the same address written three different ways causes problems in verification checks.

1. 1
   List every address you useRegistered office, principal office, mailing address, and each owner's home address. Note which form each one is on.
2. 2
   Match the format exactlyUse the same suite, PMB or # and ZIP+4 everywhere the same address appears.
3. 3
   Keep the proof on fileA lease, a utility bill or a Form 1583 confirmation, depending on the address type.
4. 4
   Update in the right places when it changesForm 8822-B for the IRS (source), the state's amendment or annual report for state records, and each bank or platform.

Registate forms LLCs and C-Corps with a registered agent included in every formation package, so the registered office is covered from day one. For the rest, you can add a virtual mailbox, a virtual office or a lease-backed address.

Sources

We checked every rule above on the official source in September 2026. States, the IRS, USPS and providers can change them, so confirm on the source before you file.

• U.S. Small Business Administration: Launch your business
• U.S. Small Business Administration: Register your business
• IRS: Instructions for Form SS-4 (lines 4a–7b)
• IRS: About Form 8822-B
• USPS FAQ: Commercial Mail Receiving Agency (CMRA)
• USPS Domestic Mail Manual 508 (CMRA and P.O. Box rules)
• Wyoming Secretary of State: Registered Offices and Agents Act rules, ch. 1
• Wyoming Secretary of State: registered agent FAQ
• Wyoming LLC Articles of Organization form
• Delaware Code, Title 6, § 18-104
• Stripe: Validate addresses for money management products