The Housing Affordability Index base is 100 and represents a balance point where a resident with a median household income can normally qualify to purchase a median price home. Values above 100 indicate increased affordability, while values below 100 indicate decreased affordability.
| County | Housing Affordability Index | |
|---|---|---|
| 1. | Sanders County | 90 |
| 2. | Gallatin County | 98 |
| 3. | Ravalli County | 99 |
| 4. | Flathead County | 100 |
| 5. | Park County | 103 |
| 6. | Missoula County | 108 |
| 7. | Carbon County | 112 |
| 8. | Lake County | 113 |
| 9. | Lincoln County | 114 |
| 10. | Madison County | 115 |
| 11. | Granite County | 126 |
| 12. | Jefferson County | 127 |
| 13. | Sweet Grass County | 127 |
| 14. | Silver Bow County | 130 |
| 15. | Mineral County | 130 |
| 16. | Yellowstone County | 132 |
| 17. | Lewis and Clark County | 140 |
| 18. | Beaverhead County | 140 |
| 19. | Cascade County | 142 |
| 20. | Musselshell County | 143 |
