| Index | Harlem | Montana | National |
| Cost of living | 86 | 102 | 100 |
| Groceries | 104 | 103 | 100 |
| Health care | 102 | 102 | 100 |
| Housing | 49 | 101 | 100 |
| Transportation | 101 | 100 | 100 |
| Utilities | 105 | 104 | 100 |
| Lifestyle & Entertainment | 101 | 100 | 100 |
| Household Items | 99 | 100 | 100 |
| Education & Childcare | 106 | 102 | 100 |

| Cost of living index | |
| Groceries index | |
| Health care index | |
| Housing index | |
| Transportation index | |
| Utilities index | |
| Lifestyle index | |
| Household index | |
| Educare index |
| Median Income | Per Year | Per Month | Max Budget (28% DTI) | Max Budget (36% DTI) |
| Owners | $87,833 | $7,319 | $2,049 | $2,635 |
| Renters | $60,322 | $5,027 | $1,407 | $1,810 |
| State | General Sales Tax | With Max Surtax |
| Montana | 0% | 0% |
| State | Income Tax (Low) | Income Tax (High) |
| Montana | 1% | 6.75% |
| City | Population | Cost of Living Index | National Avg. |
| Fort Belknap Agency, MT | 1,572 | 83 | 17.0% |
| Harlem, MT | 893 | 86 | 13.5% |
| City | Population | Cost of Living Index | National Avg. |
| Alpaugh, CA | 893 | 93 | 6.6% |
| Watkins, MN | 893 | 87 | 13.0% |
| Notre-Dame-de-la-Merci, QC | 893 | n/a | |
| Excel, AL | 892 | 96 | 3.8% |
| Rancho Mesa Verde, AZ | 892 | 86 | 13.8% |
| Harlem, MT | 893 | 86 | 13.5% |