Exhibit 23.1

Consent of Independent Registered Public Accounting Firm

We consent to the incorporation by reference in the Registration Statement (No. 333-150313) on Form S-8 of our report dated June 28, 2017 appearing in the annual report on Form 11-K of Mackinac Financial Corporation 401(k) Plan for the year ended December 31, 2016.

/s/ Plante & Moran, PLLC

Auburn Hills, Michigan

June 28, 2017