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Notice of Third-Party MOVEit Data Breach

A cybersecurity vulnerability with third-party software provider, MOVEit, has impacted thousands of companies, including First National 1870. Visit this page for more information.

Sunflower Bank Headquarters

8117 Preston Rd #220 | Dallas, TX 75225

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Customer Care Center

Available 8AM-8PM (CT) Monday-Friday and 8AM-4PM (CT) Saturday

Call: 888.827.5564  |  [email protected]


Assistance with:  Personal Online Banking, Business Banking Direct, Account-related questions, etc.

Treasury Management Direct Client Support

Call: 833.377.8265  |  [email protected]



CheckIt – Automated Phone Banking

Call: 800.552.2432



Credit Card & Debit Card Travel Notification

Traveling? Purchases not typical with your spending patterns may trigger fraud alerts for your protection. Call us in advance of any atypical travel or unusual purchase plans. If you are traveling internationally, beyond Canada and Mexico, you must notify us in advance if you intend to use your debit card.

Call: 888.827.5564



Report a Lost or Stolen Debit Card

Call: 800.472.3272



Mortgage Servicing

Request for Information or Notice of Errors must be sent to:

Customer Service
P.O. Box 833890
Richardson, TX 75083-3890

Call: 800.331.4799  |  [email protected]

Guardian Mortgage, a division of Sunflower Bank, N.A.


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