A dissertation is a huge undertaking, to get a high grade you will need to spend literally hundreds of hours working on it and a correspondingly large amount of time simply discussing it with other people. If there is one thing that can be absolutely guaranteed, it's that you will quickly lose count of the number of people who ask 'so what is your dissertation about?' For both of these reasons, choosing a topic which you find interesting and can talk about for hours is vitally important.
One of the most important things to keep in mind when choosing a title for your dissertation is the word limit which you will have to adhere to. It is virtually impossible to immediately choose a title which can be answered in precisely the amount of words you have at your disposal. Having too broad a topic will mean missing out important details while having a topic which is too narrow will mean you end up waffling after running out of valuable information to contribute.
Don't worry too much about getting it just right at first, the vast majority of students slightly revise the scale of their topic after they have begun working and gained a better grasp of how many words they will need, however you should keep it in mind when deciding on a subject. It's generally a good idea to limit a dissertation on banking and finance to a specific time frame and location at the very least, unless you have a more theoretical topic in mind. For example instead of 'An analysis of the banking sector's contribution to the 2007 credit crunch,' you might choose to look specifically at the American banking sector.
Obviously it's important to pick a topic which covers an area of banking and finance which you have a good understanding of and enjoy learning about. Once you've identified a few topics which fulfil these criteria then you should try and identify a subject which will grant you the opportunity to demonstrate the skills you are most proficient in. If you are fantastic at math then choose a topic which requires a lot of data analysis and statistics. Alternatively if you are better at writing long persuasive pieces then choose a more qualitative topic. By doing this you can maximise your strengths and cover your weaknesses.
To give you a head start here are four examples of banking and finance dissertation topics: