Mortgage loans are generally structured as long-term loans, the periodic payments for which are similar to an annuity and calculated according to the time value of money formulae. The most basic arrangement would require a fixed monthly payment over a period of ten to thirty years, depending on local conditions. Over this period the principal component of the loan (the original loan) would be slowly paid down through amortization. In practice, many variants are possible and common worldwide and within each country.
Lenders provide funds against property to earn interest income, and generally borrow these funds themselves (for example, by taking deposits or issuing bonds). The price at which the lenders borrow money therefore affects the cost of borrowing. Lenders may also, in many countries, sell the mortgage loan to other parties who are interested in receiving the stream of cash payments from the borrower, often in the form of a security (by means of a securitization). In the United States, the largest firms securitizing loans are Fannie Mae and Freddie Mac, which are government sponsored enterprises.
Mortgage lending will also take into account the (perceived) riskiness of the mortgage loan, that is, the likelihood that the funds will be repaid (usually considered a function of the creditworthiness of the borrower); that if they are not repaid, the lender will be able to foreclose and recoup some or all of its original capital; and the financial, interest rate risk and time delays that may be involved in certain circumstances.
Mortgage loan types
There are many types of mortgages used worldwide, but several factors broadly define the characteristics of the mortgage. All of these may be subject to local regulation and legal requirements.
The two basic types of amortized loans are the fixed rate mortgages (FRM) and adjustable rate mortgages (ARM) (also known as a floating rate or variable rate mortgage). In many countries, floating rate mortgages are the norm and will simply be referred to as mortgages; in the United States, fixed rate mortgages are typically considered "standard." Combinations of fixed and floating rate are also common, whereby a mortgage loan will have a fixed rate for some period, and vary after the end of that period.
In a fixed rate mortgage, the interest rate, and hence periodic payment, remains fixed for the life (or term) of the loan. In the U.S., the term is usually up to 30 years (15 and 30 being the most common), although longer terms may be offered in certain circumstances. For a fixed rate mortgage, payments for principal and interest should not change over the life of the loan, although ancillary costs (such as property taxes and insurance) can and do change.
In an adjustable rate mortgage, the interest rate is generally fixed for a period of time, after which it will periodically (for example, annually or monthly) adjust up or down to some market index. Common indices in the U.S. include the Prime rate, the London Interbank Offered Rate (LIBOR), and the Treasury Index ("T-Bill"); other indices are in use but are less popular.You can select the mortgage loan you require when interest rates are quite low and get it adjusted throughout the loan term.