Annual Percentage Rate or APR allows you to compare the true cost of your mortgage loan. 

It incorporates the interest rate plus fees and other costs, into a single percentage rate that helps you determine how much the mortgage will actually cost you.

This is really helpful when comparing multiple offers. If you see an offer with a much higher APR, look to see what fees are being charged. 

REMEMBER: The Lowest Rate Isn't Always the Best Deal.