Branch Network
One American Bank Locations & Branches Centerville, South Dakota
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One American Bank operates 3 branches from its headquarters in Centerville, SD, .
One American Bank branch network
All 3 branches are in SOUTH DAKOTA, across 2 cities. Sioux Falls, SD has the most of its branches, 2. Its largest office by deposits is the Sioux Falls Branch office in Sioux Falls, SD, with $158.5M (68.4% of its branch deposits). It had the same number of branches on June 30, 2025.
One American Bank at a glance
Its CET1 capital ratio was 19.42% at Q2 2026, comfortably above the 7% level required once the capital conservation buffer is included.
- Total assets, Q2 2026
- $285.2M
- CET1 ratio, Q2 2026
- 19.42%
- Deposit insurance
- FDIC
- Regulator
- FDIC
- Established
- 1883
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Deposit market share
Share of all FDIC-insured deposits held in each area, from the June 30, 2026 Summary of Deposits. Rank 1 is the largest holder. Shares are by bank charter, not by holding company.
| Area | Rank | Deposit share | Deposits |
|---|---|---|---|
| City: Centerville, SD (1 branch) | 1 of 1 | 100.0% | $35.3M |
| State: SD (3 branches) | 32 of 82 | <0.1% | $231.5M |
Ranked by total assets among banks headquartered in the state: Largest banks in South Dakota.
Share by county and metro area
One American Bank's share of FDIC-insured deposits in the counties and metro areas where it has branches, from the June 30, 2026 Summary of Deposits. Up to the ten largest of each are shown, by the bank's deposits. Rank 1 is the largest holder. Banks only: credit unions are not in the Summary of Deposits.
Counties
| County | Rank | Deposit share | Deposits | County total |
|---|---|---|---|---|
| Minnehaha, SD (2 branches) | 13 of 25 | <0.1% | $196.2M | $478.92B |
| Turner, SD (1 branch) | 4 of 5 | 10.7% | $35.3M | $329.1M |
Metro areas
| Metro area | Rank | Deposit share | Deposits | Metro total |
|---|---|---|---|---|
| Sioux Falls, SD (3 branches) | 17 of 39 | <0.1% | $231.5M | $1.13T |
| Branch | Location | ZIP | Deposits |
|---|---|---|---|
| Sioux Falls Branch | Sioux Falls, SD | 57104 | $158.5M |
| 49th St | Sioux Falls, SD | 57106 | $37.8M |
| One American Bank (main office) | Centerville, SD | 57014 | $35.3M |
Source: FDIC Summary of Deposits, June 30, 2026. How the survey works.
Regulator records: FDIC BankFind (cert 6078) · FFIEC NIC profile (RSSD 95051)