In the United States, a 401(k) plan is an employer-sponsored defined-contribution pension account defined in subsection 401(k) of the Internal Revenue Code. Employee funding comes directly off their paycheck and may be matched by the employer. There are two main types corresponding to the same distinction in an Individual Retirement Account (IRA); variously referred to as traditional vs. Roth, or tax-deferred vs. tax exempt, or EET vs. TEE. For both types profits in the account are never taxed. For tax exempt accounts contributions and withdrawals have no impact on income tax. For tax deferred accounts contributions may be deducted from taxable income and withdrawals are added to taxable income. There are limits to contributions, rules governing withdrawals and possible penalties.
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