Postal savings systems provide depositors who do not have access to banks a safe and convenient method to save money. Many nations have operated banking systems involving post offices to promote saving money among the poor.

A post office is a public facility and a retailer that provides mail services, such as accepting letters and parcels, providing post office boxes, and selling postage stamps, packaging, and stationery. Post offices may offer additional services, which vary by country. These include providing and accepting government forms, and processing government services and fees. The chief administrator of a post office is called a postmaster.