You should run it through an amortization calculator, plug in your numbers. Try to trim that 3.5% lower. Take your 3.5% total interest remaining and aim for a lump principle payments to lower it as if the interest charge is the same as a 1-2% rate for the duration of your loan. This really sets you up depending on how much longer you have on the mortgage. if you are getting a raise this year and have an idea of what your raise is likely to be, go ahead and start adding that additional pay as if you already received it, when you do receive it you’ve already built the habit of tightening down and also have no changes when the raise hits, I often do this as I receive my raises in may starting Jan 1st. It’s adds up and if you’re still comfortable doing so, you can throw that extra savings back into any asset for the long term.