Exhibit

We consent to the incorporation by reference in the registration statements (No. 333-207473 and 333-156555) on Form S-3 and the registration statements (No. 333-194083 and 333-156541) on Form S-8 of S&T Bancorp, Inc. of our report dated March 1, 2018, with respect to the consolidated balance sheet of S&T Bancorp, Inc. and subsidiaries as of December 31, 2017, and the related consolidated statements of net income, comprehensive income, changes in shareholders’ equity, and cash flows for each of the years in the two-year period ended December 31, 2017, which report appears in the December 31, 2017 annual report on Form 10-K of S&T Bancorp, Inc.