Identifiers: city · CDP
| Rank | Community | Population |
|---|---|---|
| 1 | Ontario (city), CA | 175,265 |
| 2 | Rancho Cucamonga (city), CA | 174,453 |
| 3 | Pomona (city), CA | 151,713 |
| 4 | Fullerton (city), CA | 143,617 |
| 5 | Pasadena (city), CA | 138,699 |
| 6 | East Los Angeles (CDP), CA | 118,786 |
| 7 | Downey (city), CA | 114,355 |
| 8 | West Covina (city), CA | 109,501 |
| 9 | El Monte (city), CA | 109,450 |
| 10 | Burbank (city), CA | 107,337 |
| 11 | Norwalk (city), CA | 102,773 |
| 12 | Chino (city), CA | 91,403 |
| 13 | Whittier (city), CA | 87,306 |
| 14 | Buena Park (city), CA | 84,034 |
| 15 | Alhambra (city), CA | 82,868 |
| 16 | Lakewood (city), CA | 82,496 |
| 17 | Bellflower (city), CA | 79,190 |
| 18 | Upland (city), CA | 79,040 |
| 19 | Baldwin Park (city), CA | 72,176 |
| 20 | Lynwood (city), CA | 67,265 |