— Though the fiscal cliff would cost the economy an estimated $671 billion for all of 2013, the tax hit for most people would be slight at first. The expiration of Social Security and income tax cuts would be spread throughout 2013. For taxpayers with incomes of $40,000 to $65,000, paychecks would shrink an average of about $1,500 next year but an average of just $130 in January, according to the nonpartisan Tax Policy Center.

— About a third of the tax increases wouldn’t touch most Americans. Some would hit businesses. Others, such as higher taxes on investment income and estates, and the expiration of middle-income tax credits, wouldn’t come due until Americans filed their 2013 taxes in 2014.

— If a deal seemed imminent, some experts say the Internal Revenue Service could delay the increased tax withholding that’s due to kick in. Without a deal, the top income tax rate for single people with taxable income between about $36,000 and $88,000 would rise from 25 percent to 28 percent. A delay in the increased withholding would ease the initial tax hit.

— About $85 billion in spending cuts to defense and domestic programs would take weeks or longer to take effect. That means government agencies wouldn’t cut jobs right away.