For 2018, taxpayers may only deduct interest on $750,000 for qualified residence loans taken out after Dec. 15, 2017. This new limit applies to the combined amount of mortgage and home-equity debt. In addition, the new limit applies only to loans used to buy, build or improve the taxpayer’s main home and second home, according to the IRS. Taxpayers no longer can deduct a home-equity line of credit for any purpose.

Source: irs.gov.