A defined benefit plan 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 — for example, 1 percent of average salary for the last 5 years of employment for every year of service with an employer. The benefits in most traditional defined benefit plans are protected, within certain limitations, by federal insurance provided through the Pension Benefit Guaranty Corporation (PBGC).

A Cash Balance Plan is a defined benefit plan that defines the benefit in terms that are more characteristic of a defined contribution plan. In other words, a cash balance plan defines the promised benefit in terms of a stated account balance. In a typical cash balance plan, a participant's account is credited each year with a "pay credit" (such as 5 percent of compensation from his or her employer) and an "interest credit" (either a fixed rate or a variable rate that is linked to an index such as the one-year treasury bill rate). Increases and decreases in the value of the plan's investments do not directly affect the benefit amounts promised to participants. Thus, the investment risks and rewards on plan assets are borne solely by the employer. When a participant becomes entitled to receive benefits under a cash balance plan, the benefits that are received are defined in terms of an account balance. The benefits in most cash balance plans, as 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 available to sole proprietorships, partnerships, S and C corporations, LLCs, non-profits and Government entities. Contributions are not limited and are based on a number of factors. Contributions can be calculated to provide as high as 100% of average compensation of the three highest years up to $165,000 (2004) or $170,000 (2005) of benefit per year during retirement. Defined benefit plans can usually provide greater contributions to older more highly compensated participants.