The majority of your mortgage payment goes toward paying interest. To save an astounding amount of money over the long term, choose a mortgage loan with a lower rate and a shorter payback term. A 15-year mortgage may be just what the financial planner ordered. This type of loan carries a larger monthly payment; but if your budget can withstand the jolt, you can save big bucks over the long haul.
If you are able to get a lower rate that what you currently have, you can save tens of thousands of dollars over the life of your loan. Also, most lenders don't charge as many fees to refinance a mortgage and depending on how much equity you have in your home you may be able to roll the closing costs into your new loan, still have a lower balance than your original loan, a lower rate, and a lower payment.
When lenders offer a "no-cost" loan, they may include a prepayment penalty to discourage you from refinancing within the first few years of the loan. Ask the lender offering a no-cost loan to explain all the fees and penalties before you agree to these terms.
If your new mortgage rate seems too good to be true then it probably is. Check for hidden fees in your mortgage that will make up that suspicious difference.