Exhibit 23a

Consent of Independent Registered Public Accounting Firm

We consent to the incorporation by reference in Registration Statement Nos. 33-30856, 33-38411, 33-38587, 33-44788, 333-47403, 33-30756-02, 333-02873, 333-65424, 333-107414, 33-52691, 33-58187, 333-144893 and 333-182405 of Bristol-Myers Squibb Company on Form(s) S-8 of our report dated May 25, 2017, appearing in this Annual Report on Form 11-K relating to the financial statements and supplemental schedule of the Bristol-Myers Squibb Company Employee Incentive Thrift Plan as of and for the year ended December 31, 2016.

/s/ Withum Smith + Brown, PC

Morristown, New Jersey

May 25, 2017

E-1