403(b) vs 401(k): The Differences That Matter When You Change Jobs

The offer from the hospital group is good, the role is bigger, and somewhere in the benefits pack is a line saying the retirement plan is a 403(b) rather than the 401(k) you have had for fifteen years. For most people weighing 403b vs 401k, the honest answer is that the two plans work almost the same way. The differences are in who offers them, a catch-up rule that only some 403(b) savers can use, and the investment menu, which is where the real money is won or lost.

This piece covers who can offer each plan, the 2026 contribution limits, the 15-year catch-up, the investment and fee differences, and what to do with your old account when you move between sectors.

403b vs 401k: Who Offers Which

A 401(k) is offered by for-profit employers. A 403(b) is the equivalent for the public and nonprofit world. The IRS is direct about it: only public educational institutions or 501(c)(3) tax-exempt organizations may establish a 403(b) plan, and churches can offer them too.

So if you are moving from a corporate job into a university, a hospital system, a charity or a public school district, you will usually meet a 403(b). Moving the other way, you will meet a 401(k). Neither is better in principle. Both let you put part of your salary aside before tax, or after tax in a Roth version if the plan offers one, and both let the money grow without tax until you take it out.

The 2026 Contribution Limits Are the Same

For 2026 the limits match. According to the Journal of Accountancy’s summary of the IRS adjustments, the elective deferral limit for 401(k), 403(b) and most 457 plans is $24,500, up from $23,500 in 2025. Savers aged 50 and over can add a catch-up of $8,000, and those aged 60 to 63 get a higher catch-up of $11,250.

That means the headline question in any 403b vs 401k comparison, how much you can put in, has the same answer for most people. If you are maxing out one plan today, you can max out the other tomorrow.

One wrinkle helps some public sector workers. If your employer offers a governmental 457(b) plan alongside a 403(b), the two limits are separate, so you can contribute the full amount to each. A corporate 401(k) has no equivalent partner plan.

The 15-Year Catch-Up Only a 403(b) Has

The one rule that genuinely belongs to the 403(b) is the 15-year catch-up. The IRS explains that if your plan permits it and you have at least 15 years of service with the same eligible employer, such as a public school system, a hospital or a church organisation, your limit rises by the least of three amounts: $3,000; a lifetime cap of $15,000 minus what you have already added under this rule; or $5,000 multiplied by your years of service minus what you deferred in earlier years.

In plain terms, a long-serving employee who under-saved in their early years can add up to $3,000 a year on top of the normal limit, until a $15,000 lifetime total is used. If you also qualify for the age-50 catch-up, the IRS applies the extra to the 15-year catch-up first.

The catch is in the word “same”. Fifteen years has to be with one employer, and the plan has to allow it. Someone moving into a nonprofit at fifty will not reach it for a long time. Someone leaving a university after twenty years should check whether they are giving it up.

Investments and Fees: The Difference People Miss

This is where the two plans part company in practice. A 401(k) menu is chosen by the employer and usually built around mutual funds, often including low-cost index funds. A 403(b) can be invested in annuity contracts issued through an insurance company, in custodial accounts invested in mutual funds, or, for church employees, in retirement income accounts. Many 403(b) plans offer both.

Annuity products are not wrong in themselves, but they tend to carry more layers of cost than a plain index fund, and the cost is often harder to see. The plan structure also matters. The IRS notes that governmental and certain church plans are not subject to ERISA, the federal law that sets fiduciary duties and disclosure rules for most private plans. That does not make them bad plans. It does mean you should read the fee disclosures yourself rather than assume someone has negotiated them hard on your behalf.

The practical test is simple. Find the cheapest broad stock index fund on the menu and its expense ratio. If there is one at a low cost, most of the difference between 403b vs 401k disappears. If the cheapest option is an annuity with several layers of charges, the old 401(k) may have been the better plan, and that is worth knowing before you decide where your next dollar goes. Our guide to Roth IRA vs brokerage account covers where savings can go once the workplace plan’s match is captured.

Roth Versions Exist in Both

Both plan types can offer a Roth option, where contributions go in after tax and qualified withdrawals come out tax free. Whether you get one depends on the employer, not on the plan type. Some large nonprofits offer a Roth 403(b); some smaller companies still offer only a traditional 401(k).

If the Roth choice matters to you, ask before you accept the offer rather than after. The question is the same one you would ask in any comparison of Roth and traditional saving: do you expect your tax rate in retirement to be higher or lower than it is now? People who expect a high income for the rest of their careers often split contributions between the two, so they are not betting everything on one guess about future tax rates.

The same contribution limit covers both versions combined. Putting $10,000 into the Roth side leaves $14,500 for the traditional side in 2026, before any catch-up.

The Employer Match

Both plans can carry an employer match, and the match is usually worth more than any difference in fees. A nonprofit may match less than a large corporation, or may contribute without requiring you to put anything in. Read how the match is calculated and how long it takes to vest. Our guide to reading a compensation package lists the questions to ask HR on this line, and they apply equally to both plans.

What to Do With the Old Plan When You Move

When you leave one sector for the other, you have the usual choices: leave the money where it is if the old plan allows, roll it into the new employer’s plan if that plan accepts rollovers, or roll it into an IRA. Moving between a 401(k) and a 403(b) is generally possible, because both are eligible retirement plans for rollover purposes.

The deciding factor is usually cost and choice. If the old 401(k) has cheap index funds and the new 403(b) offers mainly annuities, leaving the money in the old plan or moving it to an IRA may serve you better. If the old plan was expensive, consolidating can reduce both fees and admin. Do the rollover directly between providers rather than taking a cheque, to avoid withholding and the risk of a taxable distribution.

Keep a record of the decision and the numbers behind it. A year later you will not remember why you left a five-figure balance in an old plan, and our piece on how to get more deep sleep explains why the three in the morning version of you is not the one who should be reconstructing it.

How to Decide in Twenty Minutes

If you are choosing between two offers and the plans are part of the comparison, score them the way you would score any close call. Our decision making matrix sets out the method. For retirement plans, four criteria usually carry the weight: the match, the vesting schedule, the cost of the cheapest index option, and whether a Roth option exists.

Watch for the instinct to declare one plan type the winner. Both have strengths, which is the habit our piece on dialectical thinking is about: keep what is true in each and choose the plan that meets your actual needs. Our critical thinking exercises include a drill for checking a claim from a benefits adviser before you act on it.

Where This Fits in a Bigger Move

A move between sectors is often part of a larger career change. Some people leave a corporate role to teach, run a foundation or consult. Our guide on how to start a consulting business covers the solo route, where neither plan applies and you set up your own. If you are explaining the move publicly, our piece on what to post on LinkedIn covers how to do it without sounding like a press release.

The reading lists help too. Bill Gates has recommended books on money and behaviour for years, and our piece on Bill Gates’ reading list separates the useful ones from the rest. Our list of psychology books includes the best accounts of why people leave money in expensive accounts long after they know better. And if the new job starts earlier than the old one, our piece on Andrew Huberman’s morning routine covers how to shift a routine without losing a month to it.

Related from our newsroom: what 39 CEOs actually do before work, a sourced look at their wake times and first hours.

We are not financial advisers, so check the details of any rollover and of your own plan with someone who is. But the core of 403b vs 401k fits on one line: the limits are the same, the 15-year catch-up favours long service in the nonprofit world, and the fund menu decides most of the outcome.