NCUA-insured credit union
Sentinel — Box Elder, SD
Credit Union headquartered in Box Elder, South Dakota.
Source: NCUA call report data, data as of March 31, 2026, fetched September 5, 2026
Headquarters and contact
| Address | Po Box 700 Box Elder, SD 57719 |
| County | Meade |
| Website | not published in NCUA data |
| Phone | (605) 923-1405 |
NCUA record
| NCUA Charter | 10257 |
| Federal Reserve RSSD ID | 727183 |
| Status | Active |
| Charter type | 1 (NCUA) |
| Financials as of | March 31, 2026 |
How to find your Sentinel routing number
NCUA does not publish ABA routing numbers, and many credit unions use different routing numbers by state or by account type. The reliable places to find yours: the bottom left of a check from this credit union, the "account details" screen in its online banking, or its official website.
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Offices
| Main main office Ellsworth AFB, SD |
2723 Lemay Blvd, 57706 (605) 923-1405 9 A.M - 5 P.M Mountain Time |
| Liberty Branch Box Elder, SD |
441 N Ellsworth Rd, 57719 (605) 923-1405 Lobby: M-F 9:00 AM-5:00 PM Drive Up: M-Thursday 8:00 AM-5:00 PM Drive Up: Friday 8:00 AM-5:30 PM Drive Up: Saturday 9:00 AM-12:00 PM |
| Radar Hill Branch Box Elder, SD |
22752 Mule Deer Trl, 57719 (605) 923-1405 |
| Custer Office Custer, SD |
18 Mount Rushmore Rd, 57730 (605) 673-4416 Monday thru Thursday 9:00a.m.-5:00p.m.Friday 8:00a.m. to 5:30p.m.Saturday 9:00a.m. to 12:00p.m. |
| Hill City Office Hill City, SD |
553 E Main St, 57745 (605) 574-9596 Monday thru Friday 8:00a.m. to 5:00p.m.Saturday 9:00a.m. to 12:00p.m. |
| Triple Crown Rapid City, SD |
4011 Triple Crown Dr, 57701 (605) 923-1405 9 A.M - 5 P.M Mountain Time |
| Haines Rapid City, SD |
1430 Haines Ave Ste 101, 57701 (605) 923-1405 9 A.M - 5 P.M Mountain Time |
| Winner Winner, SD |
511 E 2Nd St, 57580 (605) 842-3581 8 A.M - 4 P.M. Central Time |
Where Sentinel has offices
Cities with the most Sentinel offices
Largest credit unions headquartered elsewhere in South Dakota
| Black Hills Rapid City | $2.37 billion |
| Dakotaland Huron | $739.56 million |
| Levo Sioux Falls | $526.57 million |
| Voyage Sioux Falls | $282.43 million |
| Highmark Rapid City | $260.08 million |
| Bluestone Sioux Falls | $212.57 million |
| Service First Sioux Falls | $210.05 million |
| Area Aberdeen | $200.24 million |
Compare before you open an account: today's CD and savings rates, the CD calculator and the savings calculator.
