Here's what I would do if my country needed this (Canada has very strong Credit Unions already, that accomplish nearly all of what you want. I actually work for

Here's what I would do if my country needed this (Canada has very strong Credit Unions already, that accomplish nearly all of what you want. I actually work for them, on online banking software): 1. Form a credit union, or partner with an existing one. This is a very good structure for a financial institution that is open and non-profit. You don't need any physical branches, you can be online only. 2. Read up on http://en.wikipedia.org/wiki/ISO_8583 http://en.wikipedia.org/wiki/ISO_8583 , check out a project like http://www.jpos.org/ http://www.jpos.org/ - this is the standard all financial institutions (and ATMs, debit terminals, etc.) use to talk to each other. 3. You'll also need the actual banking database-of-record software (banking system, banking host software are commons terms). There are some open ones already out there, I can't speak to their quality. 4. If you just want retail banking (ATM cards, current accounts, etc.) you're pretty much done. If you want to offer loans/mortgages, things get a lot more complicated.