Русско-англо-русский юридический словарь

A postal order is a financial instrument usually intended for sending money through the mail. It is purchased at a post office and is payable at another post office to the named recipient. A small fee for the service, known as poundage, is paid by the purchaser. In the United States, this is known as a postal money order. (Wikipedia)

If something is free of charge, it does not cost anything: The leaflet is available free of charge from post offices. (COBUILD Advanced English Dictionary)

‘The left luggage office is in the arrivals hall, near the post office.’ (Oxford English Dictionary)

Post Office could offer sub-postmasters a share in profits ... (BBC)