why do we need to use city and state in our addresses if ZIP codes are already linked to the city and state?

Question

why do we need to use city and state in our addresses if ZIP codes are already linked to the city and state?

In: 100

Answer 1

ZIP codes are a bit more like distribution-center numbers than direct town mappings.

Some smaller towns share ZIP codes, because there are a lot more than 99999 places.

Large cities have multiple ZIP codes, because they have multiple distribution centers.

Some very large volume companies have their own ZIP code, and then the street address doesn’t even matter, since the ZIP code maps to the mailroom already at that address (they do their own sorting/distribution, so they get a distribution center code).

So having the city, state on there helps re-confirm your wishes. Although with automated sorting, the computers just read the ZIP and go with that, you can put random other place names and states with a ZIP code that doesn’t match and it still goes to the ZIP code as long as there is a valid street address “over there” too.