How Banks Make Money? Banks borrow money at a slightly higher rate than the rate posted by the Bank of Canada. They in turn, lend money for a higher interest rate via mortgages and loans. The difference between the interest rate at which the bank borrows money and the amount they receive via client mortgage payments is profit. Bank of Canada Key lending "interest" rate (aka bank rate, overnight rate): is the interest rate at which major financial institutions borrow and lend one-day (or... [read more]