Post-office box

A post-office box or post office box (commonly referred to as a PO box or a postal box) is a uniquely addressable lockable box located on the premises of a post office station.

In many regions, particularly in Africa and the Middle East, there is no 'door to door' delivery of mail, for example, in Kenya. Consequently, renting a PO box has traditionally been the only way to receive mail in such countries. However, some, like Jordan, have introduced mail home delivery.

Generally, post office boxes are rented from the post office either by individuals or by businesses on a basis ranging from monthly to annual, and the cost of rent varies depending on the box size. Central business district (CBD) PO boxes are usually more expensive than rural PO boxes.

In the United States, the rental rate used to be uniform across the country. Now, however, a postal facility can be in any of seven fee groups by location; in addition, certain customers qualify for free box rental, usually because the Postal Service doesn't offer carrier-route delivery to their physical addresses.

In the United Kingdom, Royal Mail PO boxes are often little more than pigeon-holes in the secure section of a sorting office, and are accessible only by staff. In such cases, the renter of the PO box will be issued with a card showing the PO box number and delivery office name, and must produce this to the desk staff when collecting mail. For an additional fee, the Royal Mail will deliver received items to the renter's geographical address.

Some private companies (e.g., United Parcel Service (UPS) and commercial mail receiving agencies, also offer similar services of renting a mailbox in a public location. The difference with an official PO box is that mail sent there is addressed to a street address (along with the box number), instead of just addressed to "PO Box CSX".

The quantity of post office boxes in a station varies widely. Stations of small areas are often equipped with fewer than 100 boxes, while stations in a central business district (CBD) area may offer a combined quantity of over 200,000 post office boxes.

Post office boxes are usually mounted in a wall of the post office, either an external wall or a wall in a lobby, so that staff on the inside may deposit mail in a box, while a key holder (some older post office boxes use a combination dial to open their box instead of a key) in the lobby or on the outside of the building may open his or her box to retrieve the mail.

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Wikipedia