Most retirement plans, including 401(k), profit-sharing and 403(b), are called defined contribution (DC) plans because the amount "contributed" to the plan is known or "defined." The employee or the employer (or both) contribute to the employee's individual account at a set rate, such as 5 percent of pay. The future benefit of that individual account is not defined — the final account balance will fluctuate depending on how the underlying investments perform.
A defined benefit plan, on the other hand, promises a specified monthly benefit at retirement. The plan may state this promised benefit as an exact dollar amount, such as $100 per month at retirement. Or, more commonly, it may calculate a benefit through a plan formula that considers such factors as salary and service. The benefits in most traditional defined benefit plans are protected, within certain limitations, by federal insurance provided through the Pension Benefit Guaranty Corporation (PBGC).
Defined benefit plans are qualified retirement accounts that pay a specific benefit at the plan holder's retirement age. Defined benefit plans can be an excellent option for companies with older employees who wish to accumulate assets rapidly, or for high-revenue companies and small businesses that can afford to make higher contributions.