When calculating tax savings from mortgage interest, should you use your marginal tax rate or average tax rate
The TurboTax and HR Block quick calulators appear to use average tax rate to determine tax savings. Our average tax rate was 15% this year. Most other calculators specifically designed for calculating mortgage interest tax savings use marginal tax rate, which for us is 25%. Which are we supposed to use for an accurate estimation of our tax savings? We’re thinking of buying a home and this weighs heavily in our decision process.
Marginal rate. If you are only a little bit into that bracket though, the actual savings might not be that much, since some would only have been taxed in the next lower bracket. But don’t forget, if you itemize you no longer get the standard deduction, so your only real tax savings is based on the amount your itemized deductions are OVER your standard. So the estimate of tax savings is (total expected itemized deductions minus standard deduction) times tax bracket.