Exhibit 23.3

Raymond Chabot

Grant Thornton LLP

Suite 2000

National Bank Tower

600 De La Gauchetière Street West

Montréal, Quebec

H3B 4L8

Consent of Independent Registered    T 514-878-2691

Public Accounting Firm

We have issued our report dated June 9, 2021, with respect to the consolidated financial statements of Alithya Group inc. (the “Company”) for the year ended March 31, 2021, included as an Exhibit to the Annual Report of the Company on Form 40-F for the year ended March 31, 2022, which is incorporated by reference in this Registration Statement on Form S-8.

We hereby consent to the incorporation by reference of said report in this Registration Statement on FormS-8.

Montréal, Canada

June 17, 2022

Member of Grant Thornton International Ltd rcgt.com