Contact Us

For security purposes, you must call us to reset your online banking username, password or security questions.

Routing Number


Phone Numbers

Main: 605-923-1405
Toll-Free: 888-923-1400
Overseas DSN: 675-6303
Fax: 605-923-3960


  • Remember that email communication is not encrypted. Therefore, do not send confidential information or instructions to us via email.

Will You Be Traveling With Your Card?

If you will be traveling outside of your normal area of debit or credit card use, please let us know so your cards won’t be blocked or flagged for unusual activity. Give us a call at least 48 hours in advance to let us know the dates and locations you will be traveling and to verify we have correct phone numbers to reach you. Have a safe trip!

Report Lost or Stolen Card

Mon – Fri 7:30 am – 5:30 pm MT
605-923-1405 or 888-923-1400

After Business Hours

Lock Your Card

Login to our Mobile App and select “Manage My Cards” in the More Menu. You can see your recent activity and temporarily lock and unlock your cards at any time for any reason.

Card Transaction Assistance

Mon – Fri 7:30 am – 5:30 pm MT
605-923-1405 or 888-923-1400

After Hours Assistance

Activate Your Card


Change Your PIN

If you know your current PIN, you can visit any Sentinel ATM to get a new PIN for your Sentinel ATM, Debit and chip-enabled Credit Cards.

If you forgot your PIN or would like a new PIN, you can call 877-746-6746, anytime, to change the PIN for any of your Sentinel cards. Your new PIN will be available within two business days.

Get Card Alerts

Add an extra layer of security against fraud to your Sentinel Federal Credit Union credit cards and debit cards with SFCU Guardian Text Alerts. Learn more about Guardian Text Alerts.

Mailing Address

Sentinel Federal Credit Union
PO Box 700
Box Elder, SD 57719

Locations & Hours