What is a
401(k)?

Retirement Account
Educational only. TaxPlain does not provide tax, legal, or financial advice. Always consult a qualified financial advisor or tax professional about your specific situation.

A 401(k) is an employer-sponsored retirement savings account that lets you invest money for retirement while getting tax advantages from the IRS.

Think of it as a long-term investing bucket attached to your job. Money goes in from your paycheck automatically, grows over time through investments like mutual funds or index funds, and is generally meant to stay untouched until retirement age.

The biggest reason people use a 401(k): taxes. Traditional 401(k) contributions reduce your taxable income today, while Roth 401(k) contributions can allow tax-free withdrawals later in retirement.

✓ Traditional 401(k)

Contributions are made before taxes. You pay less income tax today, but withdrawals in retirement are taxed as ordinary income.

✓ Roth 401(k)

Contributions are made after taxes. You don't get a deduction now, but qualified withdrawals in retirement are generally tax-free.

📅 2024 contribution limits

Most employees can contribute up to $23,000 per year to a 401(k). If you're age 50 or older, you can contribute an additional $7,500 catch-up contribution for a total of $30,500.

The closest thing to free money

Many employers match part of your contributions. Example: "100% match up to 4%" means if you contribute 4% of your salary, your employer contributes another 4%.

That's an immediate 100% return on your money before any investment growth. Failing to contribute enough to get the full match is one of the most expensive financial mistakes employees make.

Your 401(k) usually offers a menu of investments. Most people choose combinations of:

⚠ Missing the Match

Not contributing enough to receive the full employer match means walking away from free compensation.

⚠ Cashing Out Early

Withdrawing before age 59½ usually triggers taxes plus a 10% early withdrawal penalty.

⚠ Ignoring Fees

High investment fees quietly reduce long-term growth. Even a 1% fee difference can cost tens of thousands over decades.

⚠ Never Increasing Contributions

Many workers stay at the same contribution rate for years. Gradually increasing contributions after raises can dramatically grow retirement savings.

Your 401(k) doesn't disappear when you quit or change employers. Usually you have four options:

If your employer offers a 401(k) match, contribute at least enough to receive the full match as soon as possible. If you're unsure how to invest, a low-cost target-date fund is often a reasonable default starting point for beginners. The most important factor for retirement wealth is usually consistency and time — not picking perfect investments.
Is a 401(k) the same as a pension?
No. A pension is usually funded and managed by an employer with guaranteed retirement payments. A 401(k) is primarily funded by the employee, and the retirement balance depends on contributions plus investment performance.
Can I lose money in a 401(k)?
Yes. Most 401(k) money is invested in the stock or bond market, so balances can rise and fall over time. Long-term investing historically performs better than short-term investing, but no investment is guaranteed.
Can I borrow from my 401(k)?
Some plans allow 401(k) loans, but rules vary by employer. If you leave your job before repaying the loan, the remaining balance may become taxable and subject to penalties.
What age can I withdraw money without penalties?
Generally age 59½. Traditional 401(k) withdrawals are still taxable income, but the additional 10% early withdrawal penalty usually disappears after that age.
What's the difference between a 401(k) and an IRA?
A 401(k) is employer-sponsored with higher contribution limits. An IRA is an individual retirement account you open yourself. Many people use both together.

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