First Interstate Bank holds $27.5B in total assets and has $23.0B in deposits across 155 counties in 35 ranked markets and 14 states. Its deposit footprint is broadly distributed: the top three counties (Yellowstone County, Montana, Deschutes County, Oregon, and Minnehaha County, South Dakota) hold 18% of its deposits, and Montana accounts for 27% of the total. It is among the top three banks by deposits in 55 of the 155 counties where it operates. Figures are from the FDIC Summary of Deposits as of June 30, 2025, and are refreshed once a year when the next survey is released, not quarterly.
Deposits by county
Data as of June 30, 2025 (FDIC Summary of Deposits)
| County | Deposits | County’s % of Bank’s Deposits | Bank’s % of County Deposits | Branches |
|---|---|---|---|---|
| Yellowstone County, MT | $2.0B | 8.5% | 26.6% | 9 |
| Deschutes County, OR | $1.1B | 4.9% | 22.5% | 9 |
| Minnehaha County, SD | $965M | 4.2% | 0.3% | 10 |
| Missoula County, MT | $825M | 3.6% | 22.4% | 3 |
| Ada County, ID | $791M | 3.4% | 5.4% | 10 |
| Gallatin County, MT | $684M | 3.0% | 13.6% | 4 |
| Flathead County, MT | $663M | 2.9% | 17.4% | 7 |
| Douglas County, NE | $651M | 2.8% | 2.0% | 8 |
| Pennington County, SD | $622M | 2.7% | 19.2% | 7 |
| Spokane County, WA | $589M | 2.6% | 4.2% | 8 |
| Natrona County, WY | $589M | 2.6% | 23.4% | 3 |
| Polk County, IA | $549M | 2.4% | 1.8% | 5 |
| Fremont County, WY | $486M | 2.1% | 46.6% | 2 |
| Cascade County, MT | $482M | 2.1% | 23.3% | 3 |
| Lewis and Clark County, MT | $428M | 1.9% | 18.0% | 3 |
| Kootenai County, ID | $406M | 1.8% | 8.4% | 5 |
| Teton County, WY | $389M | 1.7% | 14.9% | 2 |
| Campbell County, WY | $354M | 1.5% | 25.1% | 2 |
| Sheridan County, WY | $330M | 1.4% | 24.3% | 2 |
| Jackson County, OR | $316M | 1.4% | 6.9% | 5 |
| Albany County, WY | $304M | 1.3% | 36.1% | 1 |
| Lancaster County, NE | $284M | 1.2% | 2.0% | 7 |
| Lawrence County, SD | $275M | 1.2% | 31.1% | 4 |
| Boulder County, CO | $264M | 1.1% | 2.2% | 6 |
| Laramie County, WY | $253M | 1.1% | 8.7% | 2 |
| Canyon County, ID | $251M | 1.1% | 8.9% | 2 |
| Meade County, SD | $244M | 1.1% | 52.9% | 1 |
| Pinal County, AZ | $240M | 1.0% | 7.2% | 4 |
| Park County, MT | $223M | 1.0% | 38.7% | 2 |
| Sarpy County, NE | $216M | 0.9% | 6.6% | 3 |
| Codington County, SD | $206M | 0.9% | 13.5% | 2 |
| Josephine County, OR | $203M | 0.9% | 10.0% | 2 |
| Pima County, AZ | $179M | 0.8% | 1.0% | 1 |
| Brown County, SD | $177M | 0.8% | 9.0% | 2 |
| Webster County, IA | $165M | 0.7% | 17.0% | 2 |
| Marshall County, IA | $159M | 0.7% | 11.0% | 2 |
| Custer County, MT | $151M | 0.7% | 17.8% | 1 |
| Denver County, CO | $150M | 0.7% | 0.3% | 2 |
| Rosebud County, MT | $141M | 0.6% | 49.2% | 2 |
| Story County, IA | $138M | 0.6% | 4.4% | 3 |
| Lake County, MT | $136M | 0.6% | 17.1% | 1 |
| Maricopa County, AZ | $122M | 0.5% | 0.1% | 3 |
| Larimer County, CO | $120M | 0.5% | 1.2% | 3 |
| Custer County, SD | $115M | 0.5% | 76.4% | 2 |
| Jasper County, IA | $112M | 0.5% | 12.9% | 3 |
| Johnson County, WY | $110M | 0.5% | 19.0% | 1 |
| Des Moines County, IA | $109M | 0.5% | 7.3% | 1 |
| Weld County, CO | $102M | 0.4% | 1.6% | 2 |
| Carbon County, MT | $98M | 0.4% | 36.7% | 1 |
| Lane County, OR | $98M | 0.4% | 1.5% | 2 |
| Crook County, OR | $94M | 0.4% | 25.5% | 1 |
| Big Horn County, MT | $94M | 0.4% | 32.0% | 1 |
| Lincoln County, SD | $93M | 0.4% | <0.1% | 2 |
| Hood River County, OR | $91M | 0.4% | 13.2% | 1 |
| Butte County, SD | $90M | 0.4% | 29.1% | 1 |
| Johnson County, KS | $88M | 0.4% | 0.3% | 2 |
| Pottawattamie County, IA | $85M | 0.4% | 3.4% | 2 |
| Ravalli County, MT | $84M | 0.4% | 6.7% | 1 |
| Elmore County, ID | $84M | 0.4% | 29.0% | 1 |
| Holt County, NE | $83M | 0.4% | 13.4% | 2 |
| Douglas County, OR | $82M | 0.4% | 1.2% | 2 |
| Dawson County, NE | $81M | 0.4% | 5.7% | 2 |
| Grant County, SD | $80M | 0.3% | 20.9% | 1 |
| Montgomery County, IA | $74M | 0.3% | 20.5% | 2 |
| Lake County, SD | $74M | 0.3% | 16.9% | 1 |
| Gem County, ID | $72M | 0.3% | 24.1% | 1 |
| Lincoln County, OR | $71M | 0.3% | 6.0% | 2 |
| Multnomah County, OR | $71M | 0.3% | 0.2% | 1 |
| Fall River County, SD | $71M | 0.3% | 71.5% | 1 |
| Stillwater County, MT | $70M | 0.3% | 27.2% | 2 |
| Lincoln County, NE | $70M | 0.3% | 5.0% | 1 |
| Fremont County, IA | $68M | 0.3% | 28.2% | 2 |
| El Paso County, CO | $67M | 0.3% | 0.6% | 2 |
| Gila County, AZ | $63M | 0.3% | 6.8% | 1 |
| Wasco County, OR | $63M | 0.3% | 10.2% | 1 |
| Adams County, NE | $62M | 0.3% | 4.5% | 1 |
| Brule County, SD | $61M | 0.3% | 17.5% | 1 |
| Walworth County, SD | $60M | 0.3% | 14.7% | 1 |
| Wayne County, IA | $60M | 0.3% | 29.6% | 2 |
| Marion County, OR | $60M | 0.3% | 0.9% | 1 |
| Klamath County, OR | $59M | 0.3% | 5.5% | 1 |
| Custer County, NE | $56M | 0.2% | 10.7% | 2 |
| Platte County, NE | $54M | 0.2% | 3.1% | 1 |
| Glacier County, MT | $53M | 0.2% | 27.2% | 1 |
| Coos County, OR | $53M | 0.2% | 4.1% | 2 |
| Decatur County, IA | $51M | 0.2% | 27.3% | 1 |
| Potter County, SD | $50M | 0.2% | 25.1% | 1 |
| Poweshiek County, IA | $49M | 0.2% | 8.6% | 1 |
| Worth County, MO | $47M | 0.2% | 100.0% | 1 |
| Arapahoe County, CO | $44M | 0.2% | 0.2% | 1 |
| Dallas County, IA | $44M | 0.2% | 1.9% | 2 |
| Madison County, MT | $43M | 0.2% | 15.1% | 1 |
| Warren County, IA | $43M | 0.2% | 3.4% | 1 |
| Hall County, NE | $43M | 0.2% | 1.4% | 2 |
| Clarke County, IA | $41M | 0.2% | 13.0% | 1 |
| Black Hawk County, IA | $39M | 0.2% | 1.4% | 2 |
| Garfield County, NE | $38M | 0.2% | 38.7% | 1 |
| Payette County, ID | $38M | 0.2% | 7.9% | 1 |
| Buffalo County, NE | $37M | 0.2% | 1.7% | 1 |
| Mercer County, MO | $37M | 0.2% | 42.0% | 1 |
| Lincoln County, MT | $37M | 0.2% | 9.7% | 1 |
| Hutchinson County, SD | $36M | 0.2% | 7.7% | 1 |
| Pacific County, WA | $36M | 0.2% | 10.1% | 1 |
| Fremont County, CO | $34M | 0.1% | 4.6% | 1 |
| Corson County, SD | $33M | 0.1% | 52.1% | 2 |
| Clatsop County, OR | $32M | 0.1% | 3.7% | 1 |
| Page County, IA | $32M | 0.1% | 4.6% | 2 |
| Gentry County, MO | $32M | 0.1% | 13.4% | 1 |
| Spink County, SD | $31M | 0.1% | 12.8% | 1 |
| Yankton County, SD | $31M | 0.1% | 2.3% | 1 |
| Phelps County, NE | $31M | 0.1% | 6.4% | 1 |
| Roberts County, SD | $30M | 0.1% | 6.6% | 1 |
| Ringgold County, IA | $30M | 0.1% | 21.6% | 1 |
| Lucas County, IA | $29M | 0.1% | 18.2% | 1 |
| Valley County, NE | $29M | 0.1% | 12.3% | 1 |
| Whitman County, WA | $27M | 0.1% | 3.2% | 2 |
| Benton County, WA | $27M | 0.1% | 0.8% | 1 |
| Clackamas County, OR | $27M | 0.1% | 0.3% | 1 |
| Broomfield County, CO | $27M | 0.1% | 1.4% | 1 |
| Grays Harbor County, WA | $26M | 0.1% | 1.8% | 1 |
| Davison County, SD | $26M | 0.1% | 2.4% | 1 |
| Cass County, IA | $25M | 0.1% | 1.7% | 1 |
| Johnson County, IA | $24M | 0.1% | 0.5% | 1 |
| Jefferson County, OR | $24M | 0.1% | 11.3% | 1 |
| Sullivan County, MO | $24M | 0.1% | 12.3% | 1 |
| Klickitat County, WA | $23M | 0.1% | 5.5% | 1 |
| Cass County, ND | $23M | 0.1% | 0.2% | 1 |
| Scotts Bluff County, NE | $22M | 0.1% | 1.7% | 1 |
| Gage County, NE | $22M | 0.1% | 2.6% | 1 |
| Brookings County, SD | $22M | 0.1% | 1.0% | 1 |
| Day County, SD | $21M | 0.1% | 9.4% | 1 |
| Saunders County, NE | $21M | 0.1% | 2.3% | 1 |
| Taylor County, IA | $21M | 0.1% | 9.5% | 1 |
| Tama County, IA | $21M | 0.1% | 5.0% | 1 |
| Richardson County, NE | $21M | 0.1% | 5.4% | 1 |
| Mills County, IA | $20M | 0.1% | 3.2% | 1 |
| Madison County, NE | $19M | 0.1% | 0.8% | 1 |
| Dodge County, NE | $19M | 0.1% | 1.0% | 1 |
| Woodbury County, IA | $18M | 0.1% | 0.5% | 1 |
| King County, WA | $18M | 0.1% | <0.1% | 1 |
| Jefferson County, CO | $18M | 0.1% | 0.1% | 1 |
| Santa Cruz County, AZ | $18M | 0.1% | 1.6% | 1 |
| Henry County, IA | $17M | 0.1% | 3.3% | 1 |
| Otoe County, NE | $16M | 0.1% | 2.7% | 1 |
| Union County, IA | $16M | 0.1% | 3.1% | 1 |
| Cheyenne County, NE | $16M | 0.1% | 3.7% | 1 |
| Saline County, NE | $16M | 0.1% | 2.6% | 1 |
| Wahkiakum County, WA | $14M | 0.1% | 20.4% | 1 |
| Harrison County, MO | $14M | 0.1% | 3.8% | 1 |
| Grant County, WA | $14M | 0.1% | 0.8% | 1 |
| Putnam County, MO | $13M | 0.1% | 5.5% | 1 |
| Linn County, IA | $13M | 0.1% | 0.2% | 1 |
| Lyon County, MN | $12M | 0.1% | 1.1% | 1 |
| Red Willow County, NE | $12M | 0.1% | 1.9% | 1 |
| Box Butte County, NE | $12M | 0.1% | 3.6% | 1 |
“Deposits (SOD)” are deposits as reported to the FDIC at branch level in the Summary of Deposits (SOD), June 30, 2025, and are nominal. They reflect where deposits are booked and may differ from the institution’s balance-sheet total. “County’s % of Bank’s Deposits” is this county’s share of the institution’s total SOD deposits; “Bank’s % of County Deposits” is this institution’s deposits as a percent of all deposits booked in that county. Counties within a Combined or Metropolitan Statistical Area link to their full profile; other counties are shown for completeness.
Browse all covered institutions in the bank directory or the banks headquartered in MT. All 293 markets and the 1,523 counties with a branch within a CSA or MSA are covered in the Market Intelligence resource. See the methodology for how each figure is built and when to expect updates, or the disclaimer for how this data should, and should not, be read.
First Interstate Bank is named on this page solely to describe publicly reported FDIC deposit data. Its appearance does not imply any affiliation between First Interstate Bank and The Executive Recruiter Group, or endorsement by either.