Are ZIP codes always 5 digits?

Related questions

1. Where is the lowest number zip code?
2. What is the first zip code?
3. What does the first number in a ZIP code mean?
4. Where does the date go on a letter UK?
5. How are UK postcodes determined?
6. What are the odds of winning postcode lottery?
7. What countries are in the UK?
8. How do I dial USA from UK?
9. How do you dial a UK number from the UK?
10. Where do zip codes start?

Tags

1. #stands
2. #first
3. #digit
4. #codes
5. #refer
6. #precisely
7. #after
8. #extended
9. #digits
10. #format
11. #additional
12. #basic
13. #improvement
14. #later
15. #still
16. #group
17. #introduced
18. #delivery
19. #postal