Ogbonnaya graduated from the Institute of Management and Technology, Enugu with an HND (Distinction) in accounting. He also holds B.SC in Banking & Finance from Olabisi Onabanjo University, Ago-Iwoye, and MBA (Financial Management) from Lagos State University.
Onu began his working career at Ernst & Young (Chartered Accountants), where he rose to the post of Audit Senior. He later joined Zenith Bank Plc and worked in various areas in the bank including Business Development, Branch Management, and as Head of Operations of Key branches. An avid reader and prolific writer, Mr. Onu has attended different courses on management development and financial management. He is also an Associate Member of the Institute of Chartered Accountants of Nigeria (ICAN).
He was the Chief Operating Officer of Olive Microfinance Bank Limited, from where he joined Masters Energy Oil & Gas Ltd. as Group Finance Controller before being re-assigned to his present position.