WASHINGTON — More families with higher incomes could claim the popular child tax credit under a bill that won approval Friday in the House.
But in a dispute that divides Republicans and Democrats, millions of the poorest low-income families would lose the credit in 2018, when enhancements championed by President Barack Obama are set to expire.
The bill would gradually boost the amount of the $1,000-per-child tax credit by tying it to inflation, so it would go up as consumer prices rise. It also aims to make a dent in illegal immigration by prohibiting people without Social Security numbers from claiming a portion of the credit reserved for low-income families.
With nearly all Republicans voting in favor and most Democrats opposed, the bill cleared the House by a vote of 237-173. Colorado’s delegation voted along party lines.
The White House threatened to veto the bill, even though the Democratic-controlled Senate is unlikely to pass it.
About 37 million taxpayers claimed the credit in 2012, reducing their tax bills by nearly $57 billion.
House Republicans say the bill would strengthen the tax credit by increasing it as inflation rises and by making it available to more middle-income families.
The White House said the bill favors high-income taxpayers over the poor, while adding $90 billion to the budget deficit over the next decade.
Five million of the poorest low-income families would lose the credit in 2018, the White House said. An additional 6 million low-income families would see the amount of their tax credits reduced.
The house bill
• Indexes the credit amount to inflation, so it would gradually rise above $1,000 as consumer prices go up.
• Increases the income limit for married couples from $110,000 to $150,000. Under the bill, the credit would gradually be reduced for married couples making more than $150,000. It would be reduced to zero for married couples making more than $170,000.
• Indexes the income limits to inflation, so they would gradually increase as consumer prices rise.
• Requires low-income families receiving payments under the child tax credit to provide the Social Security number of at least one parent.



