The tax reform changes that were implemented for 2018 lowered several tax income brackets, so even with the change in standard versus itemized deductions, the overall income tax rates are lower. Because the income tax rates were lower, the IRS lowered the withholding tables, so employers withheld less in taxes in 2018 than in 2017. Compare the amount of taxes withheld as a percent of your income for the two years to see if this affected you. Plus, see more information below as to why your refund may have been lower this year:
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