Can I use a commercial mailbox when registering a sole proprietorship?

Depends on the state but generally a CMRA works fine. The Catch is you have to fill out the USPS form 1583 so the mailbox place knows who you really are. That doesn't make it public, it's just KYC for them.

This comes up a lot and the answer is usually 'yes for the mailing address, no for the physical address line.' Most forms make a distinction. If there's only one address field sometimes people just use the mailbox and nobody blinks.

I did exactly this. Sole prop, used a UPS Store box, filed the DBA, no issue. The only annoying part was the bank wanting a 'physical' address later, so I used my actua home for the bank and the box for the state. Not exactly airtight privacy but it kept the public record clean.

Sole prop doesn't really hide you the way an LLC might anyway, so temper expectations. Your name is going on it regardless. The address is the only piece you're actually shielding

Fair point. I know the name is public no matter what, the address is really all I'm trying to keep off the record. Appreciate the 1583 heads up.

Careful with some of the cheap mailbox places. A few of them flat refuse to accept legal service or state mail, which can bite you if you ever get sued or get official notices. Ask before you sign up, not after.

Second this. Mine said they'd accept state mail but 'not court documents.' Read the actual agreement, it's usually buried in tiny print on page 4.

Unrelated but is anyone else weirded out that a 'private' mailbox requires you to hand a stranger your ID and a copy of your ID for the file? Always felt a little backwards to me, though.

That's federal law, not the store being nosy. Blame the Patriot Act. No ID, no box.