The wrong question, then the right one
People ask “401(k) or IRA” like it is a fork in the road. It is not. You can fund both in the same year, with separate limits: $24,500 for the 401(k) and $7,500 for the IRA in 2026, per the IRS, plus catch-ups of $8,000 and $1,100 from age 50.
The real question is sequencing: which account gets your next dollar? That one has a clean answer, and it depends on whether the dollar triggers a match.
What each account does best
The 401(k) brings three advantages. The match, where employers add money when you contribute, which is an instant return no investment can promise. The limit, more than three times the IRA’s. And the automation, since payroll deduction saves the money before you ever see it, which is quietly the most effective behavioral trick in personal finance.
The IRA brings the other three. Freedom: you pick the broker and choose from the entire market of funds instead of a plan menu that might be one committee’s mediocre shortlist. Portability: the account follows you through every job change. And, often, cost: an IRA at a low-cost broker can charge a fraction of what an expensive plan menu skims.
That last point deserves numbers, because fees are where good plans and bad plans separate. The Department of Labor’s guide to plan fees runs the example: over a 35-year career, an extra one percentage point of annual fees cuts the final balance by 28%. Same worker, same contributions, same markets. If your plan’s funds charge around 1% or more while a broad index fund elsewhere charges a few hundredths of a percent, your plan is expensive, and the IRA’s case gets much stronger after the match.
One IRA caveat: at higher incomes, being covered by a workplace plan phases out the traditional IRA deduction (between $81,000 and $91,000 for single filers in 2026, per the IRS). In that zone, a Roth IRA, if your income permits one, usually becomes the better IRA flavor.
The order of operations
Here is the sequence that uses each account for what it is best at.
First, contribute to the 401(k) up to the full employer match. Every formula differs, but the principle does not: matched dollars are part of your pay, and unclaimed match is a voluntary pay cut. This step outranks everything, including most debt payoff.
Second, fund the IRA. After the match is captured, the next dollars generally do better where the menu is open and the fees are lowest. For most people that is an IRA at a major broker, invested in a broad, cheap index fund or target-date fund.
Third, go back to the 401(k). Once the IRA’s $7,500 is full, the 401(k)‘s big limit becomes the asset. Raise the payroll percentage and let automation do the rest.
Two exceptions flip step two. If your 401(k) menu is genuinely cheap, with index funds at rock-bottom expense ratios, there is no fee reason to leave, and the simplicity of one account is worth something. And if you will not actually open and automate the IRA, the 401(k)‘s payroll deduction beats a theoretical IRA every time. The best account is the one that gets funded.
How do you know if your plan is cheap? Pull the fund lineup, find the expense ratio column, and compare it to a broad index fund at any major broker. Under a quarter of a percent on the core funds is fine. Around one percent is a quiet tax on your retirement.
Step zero, which outranks all of it
Before either account takes a dollar beyond the match, check the foundation. Retirement money is locked money. Early withdrawals generally cost income tax plus a 10% penalty, which makes both accounts terrible places to store your margin for emergencies.
So build the margin separately. Three to six months of expenses in a high-yield savings account is what lets your 401(k) and IRA do their one job, compounding untouched for decades, without ever being raided to fix a transmission. Cash buffer, then match, then IRA, then back to the 401(k). Write the sequence down, automate each step, and the 401(k)-versus-IRA debate quietly resolves itself: both, in the right order.