The core difference: who controls the money and when you get it

A pension and a 401(k) are not the same thing, though both are retirement accounts. The main difference is who puts money in and who decides how much you receive. With a pension, your employer puts money in and guarantees you a fixed monthly payment for life once you retire. With a 401(k), you put your own money in, your employer may match part of it, and you decide how much to withdraw — there is no may provide amount.

A pension is a defined benefit plan. That means the benefit — the amount you receive each month — is defined in advance based on a formula. Usually the formula uses your salary, how long you worked there, and your age. You do not manage the investments; the employer does. A 401(k) is a defined contribution plan. You contribute a set amount (usually a percentage of your paycheck), and that contribution is defined. But the benefit you eventually receive depends on how much you put in, how much your employer matched, and how well your investments performed.

Key Takeaways

  • A pension guarantees a fixed monthly payment for life; a 401(k) gives you a balance you must manage and withdraw from yourself.
  • With a pension, your employer funds and invests the money; with a 401(k), you choose how much to contribute and where to invest it.
  • Pensions are rare in private companies today but common in government and some union jobs; 401(k)s are the standard retirement plan most private employers offer.
  • You can have both a pension and a 401(k) if your employer offers both, or if you worked at multiple employers with different plan types.
  • Pension payments are usually not taxed until you receive them; 401(k) contributions reduce your taxable income in the year you make them.

Who funds each plan and what that means for you

With a pension, your employer contributes money to a fund on your behalf. You may also contribute, but the employer is responsible for making sure there is enough money to pay all retirees their promised amounts. The employer hires professional investment managers to grow that fund. You have no say in how the money is invested — that is the employer's job and risk.

With a 401(k), you decide how much of your paycheck goes into the plan, up to a legal limit (the limit changes each year; in 2024 it was $23,500 for people under 50). Your employer may match part of what you contribute — for example, matching 50 cents for every dollar you put in, up to 3 percent of your salary. But the employer is not promising you any specific amount at retirement. You choose how to invest the money from a menu of options the plan offers, usually mutual funds and target-date funds. If your investments perform poorly, your retirement balance will be smaller.

When you can access the money

A pension typically begins paying you a monthly check once you reach a certain age and have worked there for a minimum number of years — often 55 or 62, and often after 10 or 20 years of service. The exact rules depend on the pension plan. Once you start receiving payments, they continue for your entire life, and usually for your spouse's life too if you choose a joint-survivor option. You cannot withdraw a lump sum instead; you receive the monthly payment the plan specifies.

A 401(k) is yours to withdraw from once you turn 59½, with some exceptions. If you withdraw before that age, you usually pay a 10 percent penalty plus income tax on the amount withdrawn. At age 73, you must begin taking required minimum distributions — the plan calculates a minimum amount you must withdraw each year. You can withdraw more than the minimum whenever you want. Unlike a pension, the money does not continue for life; once you spend it, it is gone.

Portability: what happens if you change jobs

If you leave a job with a pension, you usually cannot take the pension with you. Your pension stays with that employer's plan. You will receive the pension payment once you reach the plan's retirement age, based on the years you worked there. If you leave before you are vested — before you have worked there long enough to own the pension — you may receive nothing, or you may receive only your own contributions back. Vesting periods vary; some pensions vest after 5 years, others after 10.

A 401(k) is portable. If you leave your job, you can roll the 401(k) balance into a new employer's 401(k) plan, or into an Individual Retirement Account (IRA). The money stays yours and continues to grow tax-deferred. This portability is one reason 401(k)s became popular as employers moved away from pensions — workers can take their retirement savings with them.

How common each plan is today

Pensions are rare in private companies now. Most private employers stopped offering them in the 1980s and 1990s because they are expensive and create long-term obligations. Today, pensions are most common in government jobs (federal, state, and local), the military, some union jobs, and a few large private companies. If you work for a city, county, state, or federal agency, or for a union, you may have a pension.

401(k)s are the standard retirement plan in private companies. Most employers that offer retirement benefits offer a 401(k), often with a company match. Some employers offer both a 401(k) and a pension, though this is uncommon. A few employers offer neither, leaving retirement savings entirely to the employee.

Tax treatment: when you pay taxes on the money

Money you contribute to a traditional 401(k) reduces your taxable income in the year you contribute it. If you earn $60,000 and contribute $6,000 to your 401(k), you pay income tax on only $54,000. The money grows tax-free inside the account. When you withdraw it in retirement, you pay income tax on the full amount withdrawn. If your employer offers a Roth 401(k), contributions do not reduce your current taxes, but withdrawals in retirement are tax-free.

Pension contributions are usually made by the employer, not you, so they do not affect your current taxes. When you receive your monthly pension payment in retirement, you pay income tax on it as ordinary income. Some pensions offer a lump-sum payout option instead of monthly payments; if you take the lump sum, you can roll it into an IRA to defer taxes, or you pay taxes on the full amount that year.

Risk: who bears the investment risk

With a pension, the employer bears the investment risk. If the pension fund's investments perform poorly, the employer must still pay you the promised amount. This is why pensions are expensive for employers and why many have closed them to new employees. The employer cannot reduce your pension if markets decline.

With a 401(k), you bear the investment risk. If you choose conservative investments and markets boom, you may have less money than someone who chose aggressive investments. If you choose aggressive investments and markets crash near your retirement date, your balance may be much smaller than you expected. You are responsible for making investment choices that match your risk tolerance and time horizon.

Frequently Asked Questions

Can I have both a pension and a 401(k)?

Yes. Some employers offer both plans. You might also have both if you worked at multiple employers — for example, a pension from a government job you held for 10 years, and a 401(k) from a private company job you held later. The two accounts are separate and work independently.

What happens to my pension if the company goes out of business?

If a private company's pension plan is underfunded when the company fails, the Pension Benefit Guaranty Corporation (PBGC), a federal agency, takes over the plan and pays benefits up to a legal limit. The limit varies by age and plan type but is usually less than the full promised amount. Government pensions are generally protected by state law and do not rely on the PBGC.

Can I take a lump sum instead of monthly pension payments?

Some pension plans offer a lump-sum option; others do not. If your plan offers it, you can usually choose between monthly payments for life or a single large payment. The lump sum is calculated to be roughly equal in value to the lifetime payments, but the math depends on life expectancy assumptions. Ask your pension plan administrator what options are available to you.

If I leave my job before vesting, do I lose my pension?

It depends on the vesting schedule. If you leave before you are vested, you typically receive nothing from the employer's contributions — only your own contributions, if you made any. Once you are vested, you own the pension benefit, even if you leave the job. Vesting schedules vary; some plans vest gradually over five to seven years, others vest all at once after a set number of years.

How do I know if my 401(k) will last through retirement?

There is no may provide. You can estimate by calculating how much you have saved, how much you plan to withdraw each year, and how long you expect to live. A common rule of thumb is the 4 percent rule: withdraw 4 percent of your balance in the first year of retirement, then adjust for inflation in later years. But this is a rough estimate, not a may provide. Consider meeting with a financial advisor to stress-test your plan against different market scenarios.