Employee contributions to a 401 (k) plan and any investment gains are subject to deferred tax. You pay taxes on contributions and earnings when savings are withdrawn. As an employee benefit, some employers will match a portion of the employee's 401 (k) plan contributions. You don't have to pay income taxes on your contributions, although you'll have to pay other payroll taxes, such as Social Security and Medicare taxes.
You won't pay income tax on 401 (k) plan money until you withdraw it. Because your employer considers your contributions when calculating your taxable income on your W-2 form, you don't need to deduct your 401 (k) plan contributions on your tax return.
