Deferred Compensation Plans: 401(k), 403(b), 457(b), and 409A Compared

By Bob Lobclaw · August 9, 2026

“Deferred compensation” just means pay you’ve earned but haven’t received (or been taxed on) yet — the payment, and the tax bill, are pushed into the future. That umbrella covers a handful of very different vehicles: 401(k)s, 403(b)s, and 457(b)s are all employer-sponsored retirement plans built around the same basic idea of setting aside part of a paycheck before tax, but each is restricted to a different category of employer. Section 409A is something else entirely — not a plan of its own, but the tax-code section that governs unfunded executive deferred-comp arrangements sitting outside the qualified-plan system. Which of these you can even use is determined almost entirely by who signs your paycheck.

The 401(k): the private-sector default

A 401(k) is a qualified retirement plan under ERISA, available to employees of for-profit companies (and nonprofits that choose to offer one instead of, or alongside, a 403(b)). Employee contributions are held in a trust legally separate from the employer’s own assets, which protects the balance from the employer’s creditors even if the company goes bankrupt. Traditional contributions go in pre-tax and grow tax-deferred; most plans also offer a Roth 401(k) option for after-tax contributions with tax-free qualified withdrawals — see the Roth IRA vs. Roth 401(k) article for how that side-by-side choice works. Many employers add a matching contribution, and larger plans are subject to annual nondiscrimination testing meant to keep them from disproportionately benefiting highly compensated employees.

The 403(b): the nonprofit and public-school cousin

A 403(b) serves employees of 501(c)(3) tax-exempt organizations — hospitals, universities, charities — along with public school employees and ministers. It shares the 401(k)’s core mechanics: pre-tax or Roth employee deferrals, optional employer contributions, and the same elective-deferral limit. The biggest structural difference is ERISA coverage: a 403(b) sponsored by a public school or other government entity is a governmental plan and falls outside ERISA entirely, while a 403(b) at a private nonprofit may or may not be ERISA-covered depending on how much control the employer exercises over it. 403(b)s also carry a legacy quirk from their original design as tax-sheltered annuities: employees with 15 or more years of service at a qualifying organization can be eligible for an additional catch-up contribution on top of the standard age-based catch-ups, worth checking for if you’ve had a long tenure at one employer.

The 457(b): government plans, and a very different nonprofit version

A 457(b) is available to state and local government employees, and separately, to a select group of highly compensated employees at certain nonprofits (a “top-hat” plan). These two flavors look similar on the surface but differ in a way that matters a great deal: assets in a governmental 457(b) must be held in trust for the employee, just like a 401(k) or 403(b), while assets in a non-governmental (top-hat) 457(b) legally remain the employer’s general assets until paid out — fully exposed to the employer’s creditors if it becomes insolvent. A nonprofit executive with a large 457(b) balance is, in effect, an unsecured creditor of their own employer. On the upside, 457(b) distributions aren’t subject to the 10% early-withdrawal penalty that applies to early 401(k)/403(b)/IRA withdrawals — a different, narrower protection than the Rule of 55 uses for 401(k)s, and one that can be lost if the balance is later rolled into an IRA. A 457(b) also has its own separate catch-up provision in the three years before normal retirement age, which can allow contributing up to double the standard limit — but that provision can’t be combined with the standard age-50 catch-up in the same year.

Stacking a 403(b) and a 457(b)

Because a 403(b) and a governmental 457(b) are governed by separate sections of the tax code, an employee with access to both — common at public universities and hospital systems, and among state and local government employees — can max out each one independently. That effectively doubles the pre-tax deferral room compared to someone with only a 401(k), which has no equivalent second bucket. It’s one of the more underused advantages available to public-sector and large-nonprofit employees.

Section 409A: unfunded promises to executives

Section 409A isn’t a retirement plan an employee elects into the way a 401(k) is — it’s the part of the tax code that regulates nonqualified deferred compensation: arrangements, typically for executives and other highly compensated employees, where an employer simply promises to pay compensation at a later date rather than funding a dedicated, protected account. Congress enacted Section 409A as part of the American Jobs Creation Act of 2004, largely in response to executives at Enron accelerating withdrawals from their deferred-comp balances in the months before the company’s collapse, while ordinary employees’ 401(k) balances (protected by ERISA’s trust requirement) had no such escape hatch.

Because a 409A arrangement is unfunded, the money isn’t set aside in a trust the way a 401(k)’s is — it remains a general, unsecured liability of the employer, exposed to creditors in a bankruptcy, whether or not the employer sets up a “rabbi trust” to hold assets informally earmarked for the promise. In exchange for that risk, 409A plans carry no IRS contribution limit at all, letting a high earner defer salary or bonus far beyond what a 401(k) or 457(b) would allow. That flexibility comes with unusually rigid timing rules: the election to defer generally must be made before the calendar year in which the compensation is earned, and the plan can only pay out on a narrow list of permitted events — separation from service, death, disability, an unforeseeable emergency, a change in control, or a fixed date set in advance. Violating those rules doesn’t just undo the specific payment; it makes the entire deferred balance under the plan immediately taxable, plus a 20% additional federal penalty tax and interest charges — a much harsher consequence than the 10% penalty on an early qualified-plan withdrawal.

Who’s eligible for what

2026 contribution limits

*A 457(b) also offers its own special catch-up in the three years before normal retirement age, which can allow contributing up to twice the base limit — but it can’t be stacked with the standard age-based catch-up in the same year, so the higher of the two generally applies rather than both together. Because a 401(k) and a 403(b) share the same elective-deferral ceiling as each other when held with different employers in the same year (an employee-level limit under Section 402(g)), while a 457(b) has its own independent limit, the 403(b)-plus-457(b) stacking described above is what lets some public-sector and nonprofit employees defer meaningfully more than a private-sector employee with a single 401(k).

The bottom line

Which of these plans you can use is dictated by your employer’s sector, not by choice: 401(k)s belong to the for-profit world, 403(b)s to nonprofits and public education, and 457(b)s to government (or a narrow slice of nonprofit executives). All three qualified plans share similar contribution limits and, in their standard form, trust-based protection from employer creditors. Section 409A sits apart from all of them — unlimited in size but unfunded in substance, useful mainly to executives who’ve already maxed out a qualified plan and are willing to accept employer credit risk in exchange for deferring far more income. Understanding which bucket your own paycheck qualifies for is the first step; the Roth vs. 401(k) comparison tool can help model the tax tradeoff once contributions start, and the RMDs article covers what eventually happens to the pre-tax balance in a 401(k), 403(b), or governmental 457(b) later in retirement.

Educational content, not personalized financial advice — see the disclaimer.