Thirty-Year Fixed Rate Mortgage
The traditional 30-year fixed-rate mortgage has a constant interest rate and monthly payments that never change. This may be a good choice if you plan to stay in your home for seven years or longer. If you plan to move within seven years, then adjustable-rate loans are usually cheaper. As a rule of thumb, it may be harder to qualify for fixed-rate loans than for adjustable rate loans. When interest rates are low, fixed-rate loans are generally not that much more expensive than adjustable-rate mortgages and may be a better deal in the long run, because you can lock in the rate for the life of your loan.

Twenty-Year Fixed Rate Mortgage
The traditional 20-year fixed-rate mortgage has a constant interest rate and monthly payments that never change. This option typically offers a lower interest rate than the 30-year fixed with the trade-off of higher monthly paments.  As a rule of thumb, it may be harder to qualify for fixed-rate loans than for adjustable rate loans. When interest rates are low, fixed-rate loans are generally not that much more expensive than adjustable-rate mortgages and may be a better deal in the long run, because you can lock in the rate for the life of your loan.

Fifteen-Year Fixed Rate Mortgage
This loan is fully amortized over a 15-year period and features constant monthly payments. It offers all the advantages of the 30-year loan, plus a lower interest rate—and you'll own your home twice as fast. The disadvantage is that, with a 15-year loan, you commit to a higher monthly payment. Many borrowers opt for a 30-year fixed-rate loan and voluntarily make larger payments that will pay off their loan in 15 years. This approach is often safer than committing to a higher monthly payment, since the difference in interest rates isn't that great.