401(k) vs. IRA: Employer Plan or Individual Account?

A 401(k) and an IRA are easy to confuse because both are tax-advantaged ways to save for retirement, both hold investments such as mutual funds, and both come in traditional and Roth tax versions. The core difference is who sets the account up. A 401(k) exists only through an employer. An IRA is yours alone, opened by you and kept with you from job to job. That single difference drives most of the others: how much you can put in, who picks the investments, and whether anyone adds money alongside you.

How a 401(k) works

A 401(k) is a retirement plan an employer offers to its employees. If your workplace offers one, you elect to have part of each paycheck sent into the plan before you receive it. Many employers add a matching contribution up to a plan-set formula, which is part of your pay that only arrives if you contribute. The plan, not you, chooses the menu of investment options, typically a limited lineup of funds, and the money grows tax-deferred in a traditional 401(k) or after tax in a Roth 401(k), if the plan offers that option.

Two practical features follow from the employer link. First, the annual limit on employee salary contributions to a 401(k) is substantially higher than the IRA limit; both limits are set by the IRS and adjusted over time, so check the current year’s figures before relying on any number. Second, access is tied to the job: you generally cannot keep contributing after you leave, though you can usually leave the balance in the old plan, roll it into a new employer’s plan, roll it into an IRA, or cash it out. Cashing out is the costly route — withdrawals before age 59½ are generally subject to income tax plus a 10% additional tax unless an exception applies. Some plans allow loans against the balance, but only if that plan’s rules permit them.

How an IRA works

An individual retirement account (IRA) is an account you open yourself at a bank, brokerage or other IRS-approved custodian. No employer is involved and no employer adds money. You generally need taxable compensation (earned income) to contribute. You choose the investments from the custodian’s much wider universe, which can include individual stocks and bonds alongside funds, so the IRA usually offers far more choice than a workplace menu.

The tradeoff is size. The annual IRA contribution limit is lower than the 401(k) employee limit, and it caps the combined amount you put into your traditional and Roth IRAs for the year; the IRS sets the limit, the catch-up amount allowed at age 50 and older, and the income phase-out ranges, and it adjusts them over time. In a traditional IRA, contributions may be deductible depending on income and workplace-plan coverage, and withdrawals in retirement are generally taxed as ordinary income, with required minimum distributions generally beginning in your 70s under current law. In a Roth IRA, contributions are after-tax, qualified withdrawals in retirement are tax-free, direct contributions are phased out above IRS income levels, and there are no required minimum distributions for the original owner. An IRA cannot lend you your own money: taking money out is a withdrawal, with the tax and early-withdrawal rules that follow.

The side-by-side difference

	401(k)	IRA
What it is	An employer-sponsored retirement plan funded mainly through payroll deductions, with investments chosen from a menu the plan provides.	An individual retirement account you open and own yourself at a bank, brokerage or other custodian, with investments you choose.
Who qualifies/gets it	Employees of an employer that offers a plan, once they meet that plan’s eligibility rules. No job with a plan, no 401(k).	Anyone with taxable compensation (earned income), subject to IRA rules. Roth IRA direct contributions and traditional IRA deductions can be phased out above IRS income levels.
Costs	Plan administration and investment fees vary by plan and are separate from the tax rules. Early withdrawals can add a 10% additional tax unless an exception applies.	Custodian and investment fees vary by provider and are separate from the tax rules. Early withdrawals of earnings can be taxed and can add a 10% additional tax unless an exception applies.
Pros	Higher annual employee contribution limit than an IRA; automatic payroll saving; many employers match part of what you put in; some plans allow loans if their rules permit.	Yours to open without an employer and to keep across jobs; much wider investment choice; no employer gatekeeping; Roth IRA has no required minimum distributions for the original owner.
Cons	Only available through a job that offers one; investment menu is limited to what the plan chose; features such as loans and Roth options depend on the plan; the account is tied to employment.	Lower annual contribution limit than a 401(k); no employer match; no loan feature — taking money out is a taxable withdrawal; traditional IRA required minimum distributions apply.

A few rules apply to both. Both offer traditional (tax later) and Roth (tax now, qualified withdrawals tax-free later) treatments, though a 401(k) offers the Roth version only if the plan includes it. In both, money is invested and can lose value — the tax advantage does not protect the investments themselves. And in both, the contribution limits, catch-up rules and income phase-outs are figures the IRS updates, so treat any dollar figure printed in a given year as temporary.

Verdict

Choose a 401(k) first if your employer offers one and matches part of your contribution: contribute at least enough to receive the full match your plan offers before looking elsewhere, because that match is additional pay for saving you were already planning to do. The 401(k) is also the cleaner choice if you want to set aside more per year than the IRA limit allows, since its employee contribution limit is higher.

Choose an IRA if you have no workplace plan, if your plan’s investment menu or fees are poor, or if you want full control over investments and an account that travels with you unchanged from job to job. It is also the usual next step after capturing an employer match: many savers use the 401(k) up to the match, then direct additional savings to an IRA for its wider choice, then return to the 401(k) if they still have room to save. Either way, this is general education, not individual financial advice; a short check of the current IRS limits for the year you contribute is part of using either account well.

Explainer based on program rules published by the Internal Revenue Service (IRS) in its retirement plan and Individual Retirement Arrangements guidance.