What is a Defined Contribution Plan?

A defined contribution plan is a retirement plan where what goes in is defined, but what comes out is not. You and often your employer contribute a set amount, the balance is invested, and whatever it grows to is what you retire on. The 401(k) is the most common example, along with the 403(b), 457(b), and the federal Thrift Savings Plan (TSP).

The name is a contrast with the older model. A defined benefit plan promises a specific monthly income in retirement and leaves the employer responsible for funding it. A defined contribution plan makes no promise about the outcome and moves the investment risk onto you.

How Defined Contribution Plans Work

You elect a percentage of salary to contribute, usually pre-tax, though many plans also offer a Roth option. Your employer may add a match, commonly something like 50% of your contributions up to 6% of pay. The money goes into investments you select from the plan’s menu, typically a short list of index funds and target date funds.

The balance grows without annual taxes. In a traditional account you pay ordinary income tax on withdrawals in retirement; in a Roth account you paid tax up front and qualified withdrawals come out tax-free.

Because there is no promised benefit, the ending balance depends on three things you can partly control (how much you contribute, for how long, and at what cost) and one you cannot (what markets do along the way).

2026 Contribution Limits

The $24,500 is a single shared ceiling across your 401(k), 403(b), and TSP contributions combined, so having two such plans does not double it. A 457(b) is the exception: it has its own separate limit under a different part of the code, which is why someone with both a 403(b) and a governmental 457(b) can defer $24,500 to each in the same year.

Two qualifications on the catch-up rows. The age-based catch-ups are available in 401(k), 403(b), and governmental 457(b) plans; nongovernmental tax-exempt 457(b) plans do not offer them, though both kinds may offer a special catch-up in the three years before normal retirement age. And starting in 2026, if your prior-year wages from the sponsoring employer exceeded $150,000, your catch-up contributions must be designated Roth where the plan offers Roth catch-ups. That rule does not reach SEP or SIMPLE plans.

The $72,000 ceiling covers contributions credited to the account for the year, including the employer match and any after-tax contributions, while excluding catch-up amounts and rollovers. It is applied per employer rather than per plan, so two plans maintained by the same employer or by related employers in a controlled group share one $72,000 limit. It also does not work the same way for a 457(b), where employer contributions count against that plan’s single $24,500 limit rather than a separate ceiling. The gap between the deferral limit and the $72,000 ceiling is what makes a mega backdoor Roth possible in plans that allow it.

Defined Contribution vs. Defined Benefit

The shift from one to the other over the past four decades is one of the largest changes in how Americans fund retirement. It moved both the risk and the decision-making onto individuals, which is why questions like contribution rate and asset allocation now sit with employees rather than with plan actuaries.

How Much Should You Contribute?

Since the outcome is not promised, the planning question becomes whether your current contribution rate produces enough. That depends on your expected return, years to retirement, and target spending, and a contribution rate that looks adequate at 30 can fall well short by 65. You can project your retirement balance against your target spending in ProjectionLab to see whether the gap closes.

Frequently Asked Questions

Is a 401(k) a defined contribution plan? Yes, and it is the most common one. So are the 403(b) for nonprofits and schools, the 457(b) for government employees, the federal Thrift Savings Plan, and profit-sharing and employee stock ownership plans.

Is an IRA a defined contribution plan? Not technically. Defined contribution plans are employer-sponsored, and most private-sector ones are governed by the Employee Retirement Income Security Act (ERISA), though governmental plans like the TSP and a state 457(b), along with some church plans, are not. An IRA works on the same principle, with contributions defined and outcomes uncertain, but you open it yourself and different rules apply.

Can I have both a defined contribution and a defined benefit plan? Yes. Some employers, particularly in the public sector, offer a pension alongside a 457(b) or 403(b). The contribution limits are tracked separately, so participating in one does not reduce what you can put into the other.

What happens to my plan if I leave the employer? The balance is yours, subject to vesting on the employer’s contributions. You can leave it in the plan, roll it into an IRA, or move it into a new employer’s plan. Your own contributions are always fully vested.