The most common loan program is the traditional fixed rate mortgage, where the monthly principal and interest payments stay the same throughout the life of the loan. Fixed rate mortgages are available from periods of 10 to 30 years and can typically be paid off at any time without penalty. They are structured in a way that enables them to pay off completely at the end of the loan term.
If you have a fixed rate mortgage, your monthly payment might vary if it is linked with an 'impound account'. Aside from the typical 'principal + interest' payments and the possible mortgage insurance premiums (asked of those who put down 20% or less when buying a home), lenders often add an extra amount of money each month to cover the prorated monthly cost of property taxes and homeowners insurance. This extra money goes in an impound account that the lender uses to pay the property tax and homeowner insurance when due. If either of these costs change, the borrower's monthly payment will then be adjusted accordingly. Nevertheless, the overall payments with a fixed rate mortgage remain stable and foreseeable.