Beginning for tax year 2018, taxpayers are limited to deducting mortgage interest on the first $750,000 of debt related to acquiring, building or substantially improving the primary or designated secondary residence that the loan is secured by.
Prior to the Tax Cuts and Jobs Act (TCJA) taxpayers that utilized itemized deductions could deduct their mortgage interest on the first $1 million of debt related to acquiring, building or substantially improving their primary or secondary residence that the loan was secured by, and any mortgage debt (such as home equity debt) that was used for any other purposes was deductible for the next $100,000 of principal.
www.schencksc.com/education-center/articles/mortgage-interest-deduction-affected-by-tax-reform
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