1. Argentina
2. Bolivia
3. Chile
4. Colombia
5. Costa Rica
6. Cuba
7. Dominican Republic
8. Ecuador
9. El Salvador
10. Equatorial Guinea
11. Guatemala
12. Honduras
13. Mexico
14. Nicaragua
15. Panama
16. Paraguay
17. Peru
18. Spain
19. Uruguay
20. Venezuela
Important Note: While Spanish is the official language in all of these countries, there are also other languages spoken within their borders.