USPS now supports a feature called "street addressing". Basically, instead of writing "PO Box #" as the address, you may write the actual street address of the same facility followed by your box number, something like "123 Main St #456". Private mailbox providers also often accept addresses like "123 Main St Apt 456", where 456 is the number of your mailbox as well.
USPS now supports a feature called "street addressing".
Keep in mind that street addressing doesn't work at all USPS locations, although it does work at most of them. You have to fill out a form with USPS or any mail addressed to that location will be returned as undeliverable.
I've found private mailbox providers to be preferable in most every way to post-office PO boxes. Private providers are "street addressed" to begin with, virtually always accept from all couriers, usually have longer hours, often can call or email you when you receive a package, etc. In most cities, there are also more of them than post offices, I suspect because it's such an easy business to start. Look around your neighborhood: copy/print shops, shipping stores, and small business supply stores probably also rent mail boxes.
I wish this was an industry with a bit more visibility. When you think about renting a "PO Box", there's a good chance that you'd be better off with a box rental from a private mail service.
Where I am (Australia) theres a whole bunch of places that'll provide "non Post Office PO boxes" who're perfectly happy for you to address things to "Suite 306" or "Apartment 306" as well as "PO Box 306" at whatever address the box is located. Fools _most_ of the "must be a real address, not a PO Box" restrictions.
(Interestingly StartSSL failed me on that once when I gave one of those as a personal address - they mailed me saying "that looks like a business address, we need a personal home address for personal identity validation") - I dunno of they Google Street-viewed it or of they've got some automated system that flagged it...)
USA is a little different. To get mail using the street address of the PO, boxholders have to sign an additional agreement, BUT:
1) it's free, and
2) they will also accept UPS/FedEx/DHL/etc shipments on your behalf for no charge! (they will sign for packages, but if "Direct" signature (the named recipient) is required, they can't accept those.)
If you just try using "UNIT #" or "APT #" or whatever, or you don't have this additional agreement signed, they can and will return to sender.
"Mailboxes etc." in the UK is a fairly widespread commercial PO box provider. I didn't realise that was their business until I found out about a local spammer using their Cambridge branch for their address :-)
