Start with what you can afford to lose from your paycheck

The amount you put into your 403(b) each paycheck is entirely your choice — your employer does not set a required contribution amount. The real question is how much you can comfortably set aside without creating a hardship in your current budget. A common starting point is 3% to 5% of your gross pay, which most people can absorb without cutting essential expenses. If that feels tight, start lower. If you have room in your budget, you can go higher.

The IRS sets a maximum: in 2024, you can contribute up to $23,500 per year to a 403(b) if you are under age 50. If you are 50 or older, you can add an extra $7,500 catch-up contribution, for a total of $31,000. These limits reset each January. Your payroll department can tell you how much you have already contributed in the current year, so you know how much room remains.

The goal is to find a percentage that builds retirement savings without forcing you to raid credit cards or skip bills. You can change your contribution amount whenever you want — most employers allow changes through their payroll system with a few days' notice.

Key Takeaways

  • You choose your own contribution amount; there is no required minimum or employer-set percentage for 403(b) plans.
  • A practical starting point for many people is 3% to 5% of gross pay, adjusted based on what your budget can handle.
  • The IRS annual limit is $23,500 per year (under age 50) or $31,000 per year (age 50 and older) in 2024.
  • You can change your contribution percentage at any time, so you are not locked into your initial choice.
  • Payroll can tell you how much you have contributed so far this year, helping you avoid exceeding the annual limit.

How employer matching affects your decision

Some employers offer to match a portion of what you contribute — for example, they might match 50% of contributions up to 6% of your salary. If your employer offers matching, you should contribute at least enough to capture the full match. That is information programs added to your account, and passing it up means leaving retirement savings on the table.

Check your plan documents or ask your HR department whether your employer matches contributions and, if so, what the formula is. If they match dollar-for-dollar up to 3%, you should contribute at least 3%. If they match 50 cents on the dollar up to 6%, you need to contribute 6% to get the full match. Once you are getting the full match, you can decide whether to contribute more based on your budget and retirement goals.

Balancing retirement savings with take-home pay

Every dollar you contribute to your 403(b) reduces your paycheck before taxes are calculated, which lowers your current tax bill. This is called a pre-tax contribution, and it is the default for most 403(b) plans. The upside is that you pay less income tax now. The downside is that your take-home pay shrinks, and you need to make sure you can still cover rent, food, utilities, and other essentials.

Use a straightforward calculation: if you earn $3,000 per paycheck and contribute 5%, that is $150 per paycheck going into the 403(b). Your take-home pay drops by less than $150 because you also save on taxes — typically by $30 to $50 depending on your tax bracket. The net reduction to your paycheck is usually 60% to 70% of the contribution amount.

If cutting $100 to $150 from your paycheck would make it hard to pay bills, start with 2% or 3% instead. You can increase it later when your budget has more room, or when you get a raise. There is no penalty for starting small.

What happens if you contribute too much

If you reach the annual IRS limit before the end of the year, your payroll department will stop deducting contributions automatically. You do not have to do anything — the system is designed to prevent you from going over. If you are on track to exceed the limit, payroll may contact you to confirm that you want to stop contributions for the remainder of the year, or they may straightforward halt them without asking.

The risk of over-contributing is small because payroll systems are built to track the limit. However, if you have multiple 403(b) accounts (which is rare but possible), you are responsible for making sure your total contributions across all accounts do not exceed the limit. If you do accidentally over-contribute, the plan administrator will return the excess amount to you, usually with any earnings it generated.

Increasing contributions over time

You do not have to decide on a contribution amount and stick with it forever. Many people start at 3% or 4%, then increase by 1% each year, or increase their contribution whenever they get a raise. This approach lets you build retirement savings gradually without a sudden hit to your paycheck.

Some plans offer automatic escalation features, where your contribution percentage increases by a set amount each year unless you opt out. Check with your HR or plan administrator to see whether this option is available. If it is not, you can request a change to your contribution percentage through payroll whenever you are ready.

Roth versus pre-tax contributions

Most 403(b) plans offer both pre-tax and Roth contribution options. Pre-tax contributions lower your tax bill now but are taxed when you withdraw the money in retirement. Roth contributions do not lower your current taxes, but the money grows tax-free and withdrawals in retirement are tax-free.

For most people starting out, pre-tax contributions make sense because they reduce your paycheck less and free up cash for current expenses. If you are in a high tax bracket or expect to be in a lower bracket in retirement, Roth may be worth considering — but that is a longer conversation with a tax professional. For now, the important thing is to contribute something, and pre-tax is the simpler default choice.

Reviewing and adjusting your contribution

Once you have set a contribution percentage, check in with your budget after the first few paychecks. If you are struggling to cover bills, lower the percentage. If you have extra money left over at the end of the month, consider raising it. Your contribution is not permanent — you can change it as your life and finances change.

Some life events make a good time to review: a raise, a bonus, paying off a debt, or a change in household expenses. Each of these is a chance to adjust your 403(b) contribution without feeling the pinch as much. Over time, small increases add up to significant retirement savings.

Frequently Asked Questions

What is a reasonable starting contribution percentage?

Most financial advisors suggest 3% to 5% as a starting point for people new to retirement saving. This is low enough that most budgets can absorb it, but high enough to build meaningful savings over time. If that feels like too much, start with 2% and increase it later.

Should I contribute more if my employer does not offer matching?

If there is no employer match, the decision is purely about your budget and retirement goals. You are not leaving information programs on the table, so contribute whatever amount you can afford without hardship. Even 2% or 3% compounds significantly over decades.

Can I change my contribution amount mid-year?

Yes. Most employers allow you to change your contribution percentage through the payroll system at any time. The change usually takes effect within a few pay periods. There is no penalty or fee for making changes.

What if I get a raise — should I increase my 403(b) contribution?

A raise is a good time to increase your contribution because you are already used to living on your previous paycheck. If you get a 3% raise, consider putting half of it (1.5%) into your 403(b) and keeping the other half as increased take-home pay. This painlessly boosts your retirement savings.

Is there a penalty if I contribute less than the IRS limit?

No. The IRS limit is a ceiling, not a target. You can contribute $1,000 per year or $23,500 per year — both are perfectly legal. Contribute what makes sense for your situation.