Private mail bag
Open-knowledge reference entry
A private mail bag (PMB), locked bag or caller service is a term for a special form of postal delivery in some countries, usually a government department or large private company, which receive large volumes of mail. Private mail bag addresses are often used in countries in Africa where there may be no street delivery service.
Examples and variants
Like PO Box addresses, private mail bag addresses omit the name of the building and street, and include only the number allocated to the user.
Ford Motor Company of Australia Limited
Private Mail Bag 6
Campbellfield Vic 3061
Australia
In some cases, a private mail bag may not have a number:
University of Sierra Leone
Private Mail Bag
Freetown
Sierra Leone
It differs from PO box delivery in that whereas the holder of a PO box has to go to the post office in order to collect mail, the mail sent to a private bag is dispatched to the holder by a mail contractor.
Private bag
In other countries, particularly South Africa, New Zealand and Fiji, the term private bag is used.
University of Auckland
Private Bag 92019
Auckland 1142
In Fiji the usage is similar to New Zealand
FSC Limited
Private Mail Bag,
Lautoka
Fiji
In South Africa, the private bag number may also contain letters.
Department of Home Affairs
Private Bag X114
Pretoria 0001
Locked bag and caller service
In Australia, there are also locked bag addresses:
Special Broadcasting Service
Locked Bag 028
Crows Nest NSW 1585
In Singapore, the term locked bag service is used:
Singapore Press Holdings Limited
Robinson Road Post Office
Locked Bag Service 10
Singapore 908186
These are similar to a private mail bag, but the holder must collect the mail at the post office, like a PO box.
In the United States, this service is called caller service.
The public source identifies “Private mail bag” as open-knowledge reference entry. This brief keeps that definition visible, then builds a research path around Private, mail and Open-knowledge.
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Vocabulary and entity names are the principal evidence signals here, because they determine the precision of every later search. The source revision retrieved here is dated Aug 3, 2026. The linked authority identifier is Q7246117. None of the 0 selected statements returned an explicit reference. The first chronological checks are 1142 and 1585.
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This entry incorporates text from “Private mail bag” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.