Two limit buckets, not one limit for every workplace plan
In 2026 the basic employee elective-deferral limit is $24,500. Combine pre-tax and designated Roth salary deferrals across your 401(k) and 403(b) plans. Changing employer, splitting Roth and pre-tax, or opening another plan does not restart that personal basic limit.
A 457(b) plan has a separate $24,500 basic bucket. The important difference is that employer contributions to a 457(b) count toward that bucket too. Ordinary employer matching contributions to a 401(k) or 403(b) do not consume the employee elective-deferral bucket, although separate annual-additions and compensation limits apply.
A hospital employee with three plans
| 2026 contribution | Amount | Bucket |
|---|---|---|
| 401(k) employee pre-tax + Roth | $15,000 | Shared 402(g) |
| 403(b) employee pre-tax + Roth | $5,000 | Shared 402(g) |
| 457(b) employee | $10,000 | Independent 457(b) |
| 457(b) employer | $1,000 | Independent 457(b) |
The employee has $4,500 of shared basic room and $13,500 of 457(b) basic room. Using the remaining $4,500 in the 403(b) does not reduce the 457(b) room. Nor may the employee put $4,500 into each of the 401(k) and 403(b): those two plans share that room.
Remaining basic room and amounts above a bucket
Shared basic room = max(0, $24,500 − 401(k) employee deferrals − 403(b) employee deferrals). Separate 457(b) room = max(0, $24,500 − 457(b) employee deferrals − 457(b) employer contributions). Include contributions already made and any planned contributions you want to test, once only.
At $24,500 in a 401(k), another $1,000 in a 403(b) is $1,000 above the shared basic limit. It is not automatically an illegal excess: eligible catch-up contributions can sit above basic limits. The result deliberately labels that amount “above basic limit,” not “tax penalty.” Check with the plan administrator before treating it as a contribution to correct.
Catch-ups and plan acceptance remain separate
This is a basic-limit coordination tool. It does not add the age-50 catch-up, the higher age-60–63 catch-up, the 403(b) 15-year-service catch-up, or the 457(b) special three-year catch-up. Those rules have distinct eligibility and interactions. The separate 401(k), 403(b) and 457(b) tools provide more plan-specific planning.
SIMPLE IRA and SARSEP deferrals are not covered by these inputs. Compensation-based limits, the 415(c) annual-additions limit, governmental versus tax-exempt 457(b) distribution risks, employer-plan terms and corrective-distribution deadlines are not calculated. Room in a statutory bucket is not a guarantee that an employer plan permits the amount.
Official sources
Rules rechecked October 4, 2026. Source versions and calculation scope are stated above.