Tax accounting in the United States

U.S. tax accounting refers to accounting for tax purposes in the United States. Unlike most countries, the United States has a comprehensive set of accounting principles for tax purposes, prescribed by tax law, which are separate and distinct from Generally Accepted Accounting Principles.

The Internal Revenue Code governs the application of tax accounting. Section 446 sets the basic rules for tax accounting. Tax accounting under section 446(a) emphasizes consistency for a tax accounting method with references to the applied financial accounting to determine the proper method. So the taxpayer must choose a tax accounting method using their financial accounting method as a reference point.

Proper accounting methods are found in section 446(c)(1) to (4) which permits cash, accrual, and other methods approved by the IRS including combinations.

After choosing a tax accounting method, under section 446(b) the Secretary of the Treasury has wide discretion to re-compute the taxable income of the taxpayer by changing the accounting method to be used by the taxpayer in order to clearly reflect the taxpayer's income.

If the taxpayer engages in more than one business then it may use a different method for each business according to section 446(d).

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