Uh, it makes a difference. On a 50K loan at 6.5% for 30 years you’re spending 63K and change on interest. At 6.25% you’re spending 60K and change in interest. If you spent 3K to re-fi the loan what’s the benefit? If you would have taken the 3K in re-fi costs and applied it to the principal of the loan instead of re-fi, you would pay (depending on when you applied it, how far into the loan you are) maybe 48K and change on interest and take 4+ years off the life of the loan. This doesn’t work when you do the same thing at 500K.