The Tax Cuts and Jobs Act may make paying quarterly estimated tax payments on April 17 a little more complicated. That’s because tax law changes may have altered how much you will owe this year vs. last. Luckily, if you make the same or less this year as you did in 2017 you can use the safe harbor option. Go ahead and pay the same amounts you did last year (or 110 percent of last year if you make $150,000 or more).