1. Mexico: 128.9 million
2. Colombia: 51.2 million
3. Argentina: 45.7 million
4. Spain: 47.3 million
5. Peru: 33.9 million
6. Venezuela: 28.4 million
It's important to note that this list is based on population size. Other Spanish-speaking countries with significant populations include:
* Chile: 19.1 million
* Ecuador: 18.0 million
* Dominican Republic: 11.0 million
* Guatemala: 18.2 million
* Cuba: 11.3 million