| # | Institution | Type | Branches | Deposits | Share |
|---|---|---|---|---|---|
| 1 | First Interstate Bank | Bank | 2 | $223.4M | 36.86% |
| 2 | Bank of The Rockies | Bank | 3 | $122.9M | 20.28% |
| 3 | American Bank | Bank | 1 | $116.7M | 19.25% |
| 4 | Opportunity Bank of Montana | Bank | 1 | $58.5M | 9.66% |
| 5 | Wells Fargo Bank, National Association | Bank | 1 | $55.3M | 9.12% |
| 6 | Sky Federal Credit Union | Credit union | 1 | $29.3M* | 4.83% |
* Credit-union deposits are estimated (June total shares spread evenly across branches).
| Year | Deposits | Institutions | Branches | Leader | Top share | HHI |
|---|---|---|---|---|---|---|
| 2025 | $606.1M | 6 | 9 | First Interstate Bank | 36.9% | 2,340 |
| 2024 | $583.2M | 6 | 9 | First Interstate Bank | 39.1% | 2,438 |
| 2023 | $568.6M | 6 | 9 | First Interstate Bank | 38.5% | 2,376 |
| 2022 | $608.5M | 6 | 9 | First Interstate Bank | 39.3% | 2,422 |
Every institution above links to its profile — ratios, peer medians and this quarter’s change signals. Pro adds the full table, share movement and CSV export.