Virtual Mailbox & Form 1583 Rules in Montana
A commercial mailbox or private mailbox (PMB) service in Montana cannot serve as your LLC's registered agent address, though it may generally be acceptable as a business address—verification with your specific provider and the state is recommended. When opening a virtual mailbox at the U.S. Postal Service, you must complete Form 1583, which typically requires notarization or witnessing by the CMRA owner. Montana permits remote online notarization (RON) under its adoption of the Uniform Remote Notarization Law framework, meaning residents can often complete the entire virtual mailbox sign-up process online through an in-state RON notary.
However, notarization rules can vary depending on the CMRA provider and USPS policies, which do sometimes accept alternative witnessing by the mailbox owner in lieu of notary certification. This regulatory information changes periodically. Before opening a virtual mailbox, confirm current requirements on the official Montana Secretary of State website and the USPS Form 1583 instructions. Do not treat this overview as legal advice; consult your state's official resources or a qualified attorney for guidance specific to your situation.
How a virtual mailbox works
A virtual mailbox is a real street address at a commercial mail-receiving agency (CMRA) that scans your mail; opening one means filing USPS PS Form 1583, witnessed by a notary or the provider, with two IDs.
| Detail | As the rule stands |
|---|---|
| Can a virtual mailbox be your registered agent? | No (a PMB cannot be your registered agent) |
| Can it be your LLC business address? | Generally yes — verify |
| Online notarization (RON) for Form 1583 | Online notarization (RON) available |
| Form 1583 witnessing | Notary or CMRA-owner witness (in person or by A/V) |
| PMB designator (address line) | 'PMB <number>' or '# <number>' (USPS DMM 508.1.4) |
| Governing citation | Mont. Code §1-5-601 et seq.; USPS DMM 508.1.8 |
Opening any virtual mailbox means filing USPS PS Form 1583. The form must be witnessed — by a notary or by the mailbox provider (the CMRA owner/manager), in person or by real-time audio-video under the 2024 CMRA Clarification rule — and you supply two acceptable IDs. It is usually notarized, and the notarization can be done online via remote online notarization (RON) wherever the state allows it.
Confirm before you file. This is informational only, not legal advice. The official state Secretary of State / notary page and USPS are the authoritative sources.
Check your state's rule →Virtual address for an LLC in Montana → · Choosing a provider →
Compiled from the USPS federal baseline (DMM 508 / 39 CFR) and the state notary/RON statute, and verified June 2026. Always confirm the current rule on the official state Secretary of State / notary page before you rely on it — RON law is still moving. This state's RON status is currently medium-confidence (the exact statute section is not yet pinned), so treat the online-notarization detail as a starting point and confirm it on the official page. How we compile this. Informational only, not legal advice.