Can I Make Catch-Up Contributions To Both A 403(b) And A 457(b) In The Same Year

Yes, you can make catch-up contributions to both a 403(b) and a 457(b) in the same year because the IRS treats these plans as completely separate entities with independent contribution limits that do not aggregate.

Why 403b 457b catch-up limits don’t combine

The IRS coordination rules explicitly exclude 457(b) plans from aggregation with 403(b) plans. That is the reason these two accounts function as independent buckets. Under Internal Revenue Code Section 402(g), the elective deferral limit applies to the total of your 401(k), 403(b), and SIMPLE IRA deferrals combined. The IRS sets this limit. For the current year’s figure, always check the official IRS cost‑of‑living adjustments page. But 457(b) plans are deliberately left out of that calculation. The IRS states that a 457(b) plan is a non-qualified deferred compensation plan for governmental and tax-exempt employers. Its contribution limit operates independently from the limits that apply to qualified plans like 403(b)s. So when you contribute to a 403(b), you are using your Section 402(g) limit. When you contribute to a 457(b), you are using an independent limit under Section 457(b) that does not stack against the other. This is why a teacher or hospital employee can max out a 403(b), add an age‑50 catch‑up, and then independently contribute the full amount to a 457(b) with its own age‑50 catch‑up, all in the same tax year. The plans never share a single aggregate cap. The IRS treats each one as its own independent contribution vehicle.

The double catch-up trap people fall into

The common mistake that ruins this strategy is confusing the standard age‑50 catch‑up with the special 403(b) long‑service rule. People then try to stack both on the 403(b) side while also maxing the 457(b). The age‑50 catch‑up applies to both 403(b) and 457(b) plans. The IRS publishes the 401(k) catch-up contribution limit for 2025 and future years on its website, so you should verify the current number there. The 403(b) also has a distinct long‑service provision that allows an additional amount per year for employees with at least 15 years of service. The IRS caps the 403(b) total at a hard ceiling that already includes both catch‑ups combined. You cannot take the standard age‑50 addition and add the long‑service credit on top of it. However, you can take the full age‑50 catch‑up on the 457(b) side without any interaction with the 403(b). The trap is that some employees think they can contribute the standard deferral plus the age‑50 addition plus the long‑service credit to the 403(b), and then also contribute the standard deferral plus the age‑50 addition to the 457(b). That math is wrong. The long‑service credit is not an addition to the standard age‑50 catch‑up. It is an alternative calculation that only applies if you have not already used the full age‑50 catch‑up. The correct 403(b) maximum is the single hard cap set by the IRS, and the 457(b) maximum is its own independent ceiling. You get a combined ceiling that is higher than a single plan allows, but only if you treat the long‑service rule as part of the 403(b) cap and never try to exceed it.

Calculating your total maximum contribution

To see the true combined ceiling, start with the standard elective deferral limit. The IRS sets this base number each year, and you must confirm it on the official IRS site because a price is a fact with an expiry date. Your 403(b) allows an additional age‑50 catch‑up. If you have 15 years of service you can add more under the long‑service provision, up to the hard cap the IRS defines. Your 457(b) also allows an age‑50 catch‑up, bringing that plan to its own independent ceiling, with no special service‑based addition. So the maximum you can contribute to both plans is the combined total of the 403(b) hard cap and the 457(b) hard cap. You must track these independently because the 403(b) limit is a combined cap that includes both catch‑ups, while the 457(b) limit stands alone. If you are 50 or older and work for a public school or non‑profit, you can write two distinct payroll deferral authorizations, one for each plan. Your employer will report them on distinct W‑2 forms. The IRS will not flag you for overcontributing because the 457(b) is excluded from the 402(g) aggregation test. But you must still ensure that your 403(b) contributions never exceed its hard cap and your 457(b) contributions never exceed its own ceiling. Failure to do so will trigger a 10% excise tax on the excess amount. You will have to withdraw it by April 15 of the following year to avoid double taxation.

Frequently asked questions

Do I need to make distinct deferral elections for each plan?

Yes, you must submit a distinct salary reduction agreement to each plan administrator. Your 403(b) election goes to your employer’s 403(b) provider. Your 457(b) election goes to the 457(b) plan administrator. They never share information about your deferral percentages.

What happens if I accidentally overcontribute to one plan?

If you exceed the 403(b) limit, you must request a corrective distribution of the excess by April 15 of the following year. You will owe income tax plus a 10% excise tax on the earnings. The 457(b) has the same correction process. Because the limits are independent, an excess in one plan does not affect the other.

Can I use the long‑service rule on the 403(b) and the age‑50 catch‑up on the 457(b) in the same year?

Yes, you can use both, but you cannot use the long‑service rule on the 403(b) and also take an independent age‑50 catch‑up on that same 403(b) beyond its hard cap. On the 457(b), you simply take the standard age‑50 catch‑up. The two plans never interact. This is the key distinction when comparing catch-up contributions vs. spousal IRA contributions, because a spouse’s IRA has no connection to your workplace plan ceilings.

Does my employer automatically track both limits for me?

No, most employers only track the limit for the specific plan they administer. You are responsible for monitoring your own contributions across both plans. You should check your pay stubs monthly to ensure you do not exceed either cap. The single most important rule that no competitor can claim is this: you can overcontribute to a 401(k) with catch-up amounts and face penalties, but a 457(b) plan is deliberately excluded from the 402(g) aggregation test, so its contributions never count against your 403(b) ceiling.