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The White House has estimated that if the automatic tax increases proceed, consumer spending could fall in 2013 by as much as $200 billion. Economic growth could fall by 1.4 percentage points, which could have a negative impact on the post-recession recovery.
Barring any changes, the most immediately noticeable impact at the beginning of the new year for many Americans, says Weltman, will be the fact that withholding from payroll checks will jump, because employees will pay more for Social Security taxes. Says Weltman: "That will be felt immediately."