WASHINGTON — U.S. corporations received $181 billion in income tax breaks in 2011 — as much as they paid in taxes, according to a report released Monday by the Government Accountability Office in Washington, D.C.

The majority of the forgone revenue stems from two breaks alone — accelerated depreciation for capital investment and the ability to defer U.S. taxes on profits earned overseas.

Measured in constant dollars, the $181 billion was the largest total for corporate tax breaks in any year since at least 1986, when Congress last rewrote the U.S. tax code. A provision letting companies write off 100 percent of capital expenses took effect in 2011, contributing to an increase in the amount of tax breaks.

Corporate income tax collections peaked in nominal terms in 2007 at $370 billion. They dropped during the recession as companies’ profits shrank and Congress created tax incentives to encourage investment.