Onyeche began her career as a Litigation Officer with Swift & Moore (Solicitors & Legal Consultants) in Lagos and later joined Zenith Bank Plc in 2007 as a Client Service Representative, from where she was seconded to Quantum Zenith Trustees in 2009 as a Legal Officer.
Onyeche is a member of the Nigerian Bar Association, an Associate Member of both the Institute of Chartered Secretaries & Administrators (ICSA), and the Chartered Institute of Personnel Management of Nigeria (CIPM) where she bagged the award for the Overall Best Graduating Student at the 2013 qualifying exams.