In the US, you can check the address database directly to see what the minimum required elements are that resolve to your address [0]. This is what the USPS do

In the US, you can check the address database directly to see what the minimum required elements are that resolve to your address [0]. This is what the USPS does when you mail something, they match to this database and then print a delivery barcode along the bottom of the letter. Worth noting is that the delivery barcode is all that really matters. If you write 'return to sender' on an envelope and change nothing else, then throw it in the post box, you're going to get it sent right back to you. Always take a marker and block out that barcode and enough of your original address so that it gets forced to a human. [0] https://tools.usps.com/zip-code-lookup.htm?byaddress https://tools.usps.com/zip-code-lookup.htm?byaddress