Money, money, money.Or: switch and save.When you take out a mortgage, you can do so on a variable rate (the interest rate you pay goes up at down at the lender’s command) or a fixed rate (your interest rate is fixed for a set number of years)The idea of switching is to move your mortgage to a lender with a lower rate than you currently pay so you can save on the repayments.Many lenders will also give you incentives to switch your mortgage.In theory, it’s straightforward: move your mortgage money to the lender with the best rate and lock in lower monthly repayments.