Employer sponsored retirement savings program named for the section of the Internal Revenue Code that permits it. These plans allow employees to invest pre-tax dollars that are often matched in some portion by employers. Because of their flexibility, 401 (k) s became a popular employee benefit during the 1980s. But the tax reform act of 1986 limited their use as short-term savings plans by imposing a 10% penalty on all money withdrawn before retirement. It also reduced the maximum annual contribution from $30,000 to $7000 and tightened nondiscrimination rules. Employees may still borrow the money, however, and pay themselves interest.