The Importance of Zip Codes in Marketing

The US has a population of just over 329 million people, which means on average 3,295 people have to share a zip. In Australia, it's roughly 2,500 people per postcode. The UK has a particularly unusual one, which is a mix of letters and digits. There's just over 1.7 billion possible postcodes in the UK following that format. A lot of them are used because those first letters tell you what postal region you're in.