While many tax professionals have been advising their clients to prepay the bills, there has been some uncertainty about whether the early payments really will dodge the new deduction limits. The federal tax rewrite did not explicitly say whether property taxes due in 2018, but paid in 2017 would avoid the new deduction cap. On Wednesday, however, the Internal Revenue Service announced that homeowners who pay property taxes early will be able to claim the current deduction if the taxes had been assessed, billed and paid in 2017, which Pappas said would apply in Cook County.