HARP is the acronym for the Home Affordable Refinance Program. In an effort to help stabilize the housing market, the government developed the program to help homeowner's who either did not have enough equity for a traditional refinance or who were having problems making payments on their current mortgages.
The Fannie Mae refinance program goes by 2 names: the Refi Plus or DU Refi Plus (DURP) program. It allows the refinance of a 1st mortgage up to 105% of the appraised value of the property. Junior liens may be subordinated to an unlimited combined loan to value. The Fannie program has similar pricing adjustments to a normal refinance program. You are able to refinance a Fannie loan with any Fannie lender offering the program.
The Freddie Mac program is known as the Relief Refinance Mortgage. It only allows you to finance (roll in) $2,500 in closing costs, but there are far fewer pricing adjustments. With the Freddie program, your loan has to end up with the same lender that currently has your loan. Again, you may go up to 105% of the value of your home and junior liens may be subordinated.
If you are a homeowner with a Fannie Mae or Freddie Mac owned home, and you have no mortgage lates in the last 6 months (no more than 1 late in the past 12 months) you can refinance down to the 4% range on a 30 year fixed, using potentially no appraisal, and reduced to no income documentation.
You must have originated your existing loan before 6/1/2009, and must not have previously done a HARP loan (program started April 2009). Your loan must be have been securitized by Fannie Mae or Freddie Mac, and their websites allow you to enter your address to find this out.
Fannie Mae Loan Lookup Tool: http://www.fanniemae.com/loanlookup/
Freddie Mac Loan Lookup Tool: https://ww3.freddiemac.com/corporate/
More information may be found at www.MakingHomeAffordable.gov