Simply put, higher tax rates kick in at lower income levels for married couples than for cohabiting singles. That's the nature of the marriage penalty -- it causes approximately 21 million American couples to pay an average extra tax bill of $1,400.

The Heritage Foundation's Daniel J. Mitchell is of the opinion that only a flat tax can end the marriage penalty -- and that is not in the political cards at this point. So he is suggesting four short-term solutions that would help alleviate the tax pains of married couples.

• Letting couples choose whether to file individual returns -- as nine states and the District of Columbia already permit -- would result in an annual tax cut of about $30 billion, even though couples would have to figure their taxes both ways to determine which would produce a saving.

• Requiring couples to file individual returns would take care of the marriage penalty -- but taxes on couples with non-working spouses would go up, because the standard deduction would be only $4,250 for a family with one wage earner versus more than $7,000 now.

• Give second earners deductions or credits worth perhaps 10 percent of the earnings of the lower-income spouse.

• Raise the standard deduction for married couples to double the level for single filers -- a move which would cut taxes by more than $25 billion annually.

Mitchell recommends the last option. The tax code allowed single taxpayers a deduction of $4,250 in 1998. A marriage-neutral tax code therefore would allow married couples to protect $8,500 of their income with the standard deduction; instead, married couples are allowed to deduct only $7,100.

Source: Daniel J. Mitchell, "How To Fix The Marriage Penalty In The Tax Code," Backgrounder No. 1250, February 8, 1999, Heritage Foundation, 214 Massachusetts Avenue, N.E., Washington, D.C. 20002, (202) 546-4400, and "The Marriage Penalty Is a Tax on Love," Investor's Business Daily, February 12, 1999.

For text http://www.heritage.org/Research/Taxes/BG1250.cfm