WASHINGTON — A potential casualty of the “fiscal cliff" standoff is the ability of Congress to adjust an outdated tax code provision that could significantly boost what millions of middle-income households owe to the government.
The provision, called the alternative minimum tax, or AMT, was enacted in 1969 to make sure that the very wealthy paid some income tax.
But the threshold for the usually higher tax was not indexed for inflation, and it threatens each year to ensnare millions of people it was never intended to catch — prompting the annual congressional fix.
This year, however, the AMT is caught up in the broader fight over extending the President George W. Bush-era tax cuts and reducing government spending.
The Internal Revenue Service warned lawmakers that if they don’t act by Dec. 31, the number of people facing the AMT in April would jump to about 33 million from about 4 million who had to pay it this year.
For those who haven’t faced it before, the effect could be a shock — an average increase of about $3,700 per household, according to the nonpartisan Tax Policy Center.
Without an AMT patch, those taxpayers would be faced “with a very large, unexpected tax liability," acting IRS Commissioner Steven Miller wrote to key lawmakers this month.
Fixing the tax is a rare example of bipartisan agreement in Washington. Democrats and Republicans have joined together nine times since 2001 to make one- or two-year fixes to the annual taxable income level at which the AMT kicks in.
If no fix is made by Dec. 31, the threshold at which the AMT would kick in for the 2012 tax year will drop to $33,750 from $48,450 for individuals. The level for joint filers will drop to $45,000 from $74,450. Those are the same thresholds that existed in 1993.