The Limits Are Separate, Not Shared
If you contribute to a 401(k) or another 403(b) at a second job, those deferral limits stack together. A governmental 457(b) does not work that way. It has its own limit under a different section of the tax code, so a teacher who has access to both a 403(b) and a 457(b) can fund both, up to the full limit on each, in the same year.
For 2026, that means up to $24,500 into your 403(b) and another $24,500 into your 457(b) — $49,000 in combined deferrals before any catch-up. If you are 60 to 63 and both plans offer the higher catch-up, that combined number can reach $71,500.
What to Watch For in the Fee Environment
Some K-12 403(b) vendor lists include insurance companies offering variable annuity products, with total annual fees commonly in the 2% to 3% range and surrender charges that can run 5% to 10% over several years. Governmental 457(b) plans can also carry these products — there is no rule that one plan type is automatically cheaper than the other. What matters is the specific vendor and product you are in, not which account it happens to sit in.
Some vendor lists on either side include a low-cost, straightforward option. Whichever plan you are funding, it is worth confirming what you are actually invested in and what it costs.
The Early-Withdrawal Rule Is Genuinely Different
Distributions from a governmental 457(b) after you separate from service are generally not subject to the 10% early-withdrawal penalty that applies to 403(b) and 401(k) withdrawals taken before age 59½. If you plan to retire from teaching before 59½ and will need to draw on savings in the meantime, that difference is worth building into your plan.
Your 403(b) and 457(b) are both still taxed as ordinary income when withdrawn, on the traditional side. The 457(b) simply removes the early-withdrawal penalty layer once you have left the job.
The Catch-Up Rules Are Built Differently Too
A 403(b) offers a 15-years-of-service catch-up for long-tenured employees at certain qualifying employers. A governmental 457(b) offers a different mechanism entirely: a three-year special catch-up available in the three years before your plan's normal retirement age. They are not interchangeable, and you generally cannot layer the age-based catch-up and the 457(b) three-year catch-up in the same year — you use whichever produces the larger number.
Bottom line: these are not two versions of the same account. They stack on top of each other for contribution purposes, and only one of them lets you touch the money early without a penalty once you have left the classroom.