457(b) Contribution Limit Calculator

The plan-type toggle on this calculator isn't a minor formality — it separates two products that are governed by different sections of the tax code and carry genuinely different risk to the participant. A governmental 457(b), sponsored by a state, county, city, school district or similar public employer, is required to hold participant deferrals in a trust, custodial account, or annuity contract for the exclusive benefit of employees, which is what puts that money legally out of reach of the employer's own creditors.

A tax-exempt 457(b), sponsored by a hospital system, charity, or private university, works differently by design: the law requires it to remain unfunded, meaning deferrals sit as a bookkeeping promise on the employer's own balance sheet rather than in a segregated trust. Many tax-exempt plans use what's called a rabbi trust to actually hold the money day to day, but a rabbi trust does not protect participants from the sponsor's creditors — if the employer becomes insolvent, participants in an unfunded 457(b) stand behind the organization's general creditors in the payout line, with no special priority for their deferred compensation.

Congress's reasoning for allowing this arrangement at all was that only a narrow group of employees should be exposed to that risk, which is why tax-exempt 457(b) plans are legally restricted to a select group of management or highly compensated employees — a "top hat" plan, in ERISA's own terminology — rather than being offered broadly the way a governmental 457(b) or a 401(k) can be.

That underlying funding difference is also the actual reason the age-50 and age 60-63 catch-ups exist only in governmental plans: richer catch-up limits paired with unprotected, creditor-exposed balances would have compounded the risk for exactly the employees least equipped to absorb it.

Starting with the 2026 plan year, SECURE 2.0's Section 603 requires that catch-up contributions from higher earners be made as Roth, after-tax deferrals rather than pre-tax ones. The rule catches anyone 50 or older whose FICA wages from that employer exceeded $145,000 in the prior year, a threshold that's indexed for inflation and lands at $150,000 when applied to 2025 wages for determining 2026 status.

It reaches every catch-up type this calculator covers — the age-50 amount, the enhanced 60-63 amount, and the special three-year catch-up alike — so a high earner using any of them no longer chooses pre-tax versus Roth freely; the choice is made for them by statute.

What makes this a sharper problem for 457(b) plans specifically is a detail buried in the IRS's final regulations, issued in September 2025: 401(k) and 403(b) plans were given the option of a "deemed Roth election," which automatically routes a high earner's catch-up to Roth once they hit the regular limit without requiring the participant to do anything. That administrative shortcut was not extended to 457(b) plans. A governmental 457(b) sponsor has to build an affirmative election process instead, and a participant who doesn't make one risks having catch-up contributions rejected outright rather than silently redirected.

The IRS has allowed a good-faith compliance window through January 1, 2027 for plans still building this out, which is worth asking your HR or benefits office about directly if you're a higher earner planning to use any catch-up in 2026 — the answer varies by employer depending on how far along their plan amendment is.

The special catch-up is the least automatic of the three provisions this calculator handles, and it's the reason the "unused contribution room from past years" field exists as a manual input rather than something the calculator can derive on its own.

Unlike the age-50 or 60-63 catch-ups, which apply the moment you hit a birthday, the special catch-up requires your plan administrator to reconstruct how much of the basic limit you were entitled to defer in each earlier year of participation and how much of that room actually went unused — a figure that depends on your specific deferral history with that specific employer, not a number the IRS or this calculator can look up generically.

Plans that offer this provision typically require you to request the calculation directly, and the administrative burden is real enough that some employers, particularly smaller tax-exempt ones, choose not to offer it at all even though the law permits both governmental and tax-exempt 457(b) plans to do so.

"Normal retirement age" for this purpose isn't a fixed number either — it's defined by the specific plan document, usually somewhere between 65 and 70, or tied to when you'd be eligible for unreduced benefits under a separate pension plan if one exists, which is why the withinThreeYears toggle asks about your proximity to that plan-defined age rather than a flat calendar age.

Because the age-50 and special catch-ups are mutually exclusive within the same year, someone eligible for both should ask their administrator to run the comparison directly: it's common for the special catch-up to exceed the flat age-based amount for someone who spent early career years contributing little or nothing, but there's no way to know which is larger without that documented history in hand.