Tax bill will slash by half the number of homeowners using the mortgage deduction

  • The anticipated 57 percent drop in the number of taxpayers using the mortgage interest deduction is largely due to a near-doubling of the standard deduction.
  • About 20 percent of all taxpayers have used the tax break in recent years.
  • About 18 million taxpayers are expected to itemize in 2018. That's down from 46.5 million last year.

The number of homeowners who will benefit from the mortgage tax break is expected to plummet this year by more than half, according to a congressional report released on Monday.

About 13.8 million taxpayers will be able to claim the mortgage-interest deduction in 2018, down from more than 32.3 million in 2017, estimates from the Joint Committee on Taxation show. That's about a 57 percent drop.

Tax returns using mortgage interest deduction

2017 tax returns
2018 tax returns
less than $10,000 under 500 under 500
$10,000-$20,000 105,000 42,000
$20,000-$30,000 244,000 73,000
$30,000-$40,000 540,000 143,000
$40,000-$50,000 961,000 281,000
$50,000-$75,000 3,967,000 1,343,000
$75,000-$100,000 4,563,000 1,826,000
$100,000-$200,000 14,227,000 5,402,000
$200,000-$500,000 6,575,000 3,681,000
$500,000-$1 million 797,000 657,000
$1 million and over 328,000 314,000
Source: Joint Committee on Taxation estimates

Already, the deduction was not used by most taxpayers. Of the 150 million or so tax returns the IRS has received annually in recent years, just 20 percent claimed the deduction, according to research from the Urban Brookings Tax Policy Center.

The anticipated drop is largely due to the near-doubling of the standard deduction that took effect Jan. 1 under the new tax law. Fewer taxpayers are expected to itemize their deductions, which is the only way to take advantage of the tax break for interest paid on mortgages.

The new report estimates that 18 million households will itemize deductions this year, down from 46.5 million last year.

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Taxpayers would need deductions worth more than the standard deduction for itemizing to make financial sense. And with few deductions left for taxpayers to turn to, that threshold will be a harder hurdle to clear.

For example, married couples filing jointly now get a standard deduction of $24,000, up from $12,700 last year. That amount for single filers is $12,000, up from $6,350. For heads of households, it's now $18,000, up from $9,350. In combination with raising those amounts, the new tax eliminated personal exemptions.

For homeowners who will still be able to take advantage of the tax break, the interest they can write off is limited to $750,000 in loans, down from the previous $1 million.

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