Hassan qualified as a Chartered Accountant with Arthur Andersen then moved to Citibank Nigeria as a Corporate Finance Expert. He joined the Bureau of Public Enterprise (BPE) as Team Lead for reform of the telecommunications sector and concession of the ports. After BPE, he became Executive Director, Abuja Investment Company Ltd, and was later appointed CEO of ASO Savings & Loans. Hassan has served as a board member of the Nigerian Sovereign Investment Authority and the Nigeria Mortgage Refinance Corporation.