I studied Finance as an undergraduate and have worked for several years in a large Corporate Bank- But my true love is economics! Would I be suited to studying economics at post grad?
In your situation, I would recommend applying directly to graduate schools in economics. As a finance major, you have the necessary background in Calculus, Econometrics, Probability and Statistics and this sets you up to do the Maths required for a post-graduate degree (not all economics degrees require you to do Maths so you stand in good stead). You also mention that you would like to do a Research masters. These can ‘blend’ into the first year of a PhD. If you’re looking to study for a PhD then this may be really useful. Of course not all research masters lead to this – it depends on the institution and the degree – so look around.
As far as having had no formal economics education, my advice is to do as much economics reading as you can. My guess is that admissions committees will forgive you for not having taken formal economics courses if you show a real desire to catch up.
But don’t worry: you are not alone. There are many economists who come from far wider fields than yours; ‘refugees’ from fields like engineering, physics and pure maths who later discovered their interest in economics. It was not too late for them to switch, and it is probably not too late for you.
Another alternative is to perhaps do a one-year conversion course. Various universities do it. The entry requirements are normally a first or upper second class honours degree (2:1-2:2 or equivalent), though other relevant experience (including good qualifications in a less relevant subject area) may be considered. Your time in Corporate Banking as an Operations Analyst should set you up well.
The ultimate (opportunity) cost of this is that your education may end up taking a year or two longer than it would have if you had figured out your interests earlier but this is a small price to pay compared with the cost of ending up in the wrong field.