Columbia Pipeline (CPGX) 8-K 2015 FY Index to Financial Statements

Exhibit 23.3

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We consent to the incorporation by reference in Registration Statement Nos. 333-205443 and 333-207893 on Form S-3, and Registration Statement No. 333-205415 on Form S-8 of our report dated February 22, 2016, relating to the consolidated and combined financial statements of CPG OpCo LP and subsidiaries appearing in this Current Report on Form 8-K of Columbia Pipeline Group, Inc.

/s/ DELOITTE & TOUCHE LLP

Columbus, Ohio

February 22, 2016