The question behind the confusion
You've probably heard the terms — 401(k), IRA, Roth, traditional, taxable brokerage. Maybe you have accounts in several of them. And maybe you still feel unclear on what each one actually is, why it exists, and how they fit together.
That confusion is understandable. The names aren't intuitive, the rules differ, and most explanations either skip the basics or bury them in tax code. This guide draws the map plainly, in terms you can use.
The core idea: these are containers, not investments
Here's the one mental model that makes everything else clearer.
A 401(k), an IRA, a Roth — these are account types, not investments. They're containers with specific tax rules attached to them. What sits inside the container — how the money is invested — is a separate question. Two people can both have a Roth IRA and be in completely different financial positions, depending on what's inside.
The accounts differ in one fundamental dimension: when the IRS takes its cut. Pay tax now, and the account grows and withdraws tax-free. Defer the tax, and you get a break today but owe the IRS when you withdraw. Everything else — contribution limits, withdrawal rules, required distributions — flows from that distinction.
The three account categories
Traditional accounts (pretax)
Examples: Traditional 401(k), Traditional IRA, 403(b), most employer retirement plans.
You contribute money you haven't paid income tax on yet. That reduces your taxable income in the year you contribute — so if you're in the 22% bracket and contribute $6,000, you effectively reduce your tax bill by about $1,320 that year.
The money grows without being taxed along the way. When you withdraw it in retirement, you pay ordinary income tax on every dollar you take out — contributions and growth alike.
Best fit: Generally favors people who expect their tax rate in retirement to be lower than it is today. If your income will drop significantly when you stop working, deferring the tax makes sense.
Catch: Required minimum distributions (RMDs) — the IRS requires you to start withdrawing a minimum amount each year beginning at age 73, whether you need the money or not. Large traditional balances can create larger RMDs than you expected.
Roth accounts (after-tax)
Examples: Roth IRA, Roth 401(k).
You contribute money you've already paid income tax on. No deduction today. But the money grows completely tax-free, and qualified withdrawals in retirement are tax-free too — including all the decades of growth.
Roth IRAs have no required minimum distributions during your lifetime. The money can stay in the account as long as you choose.
Best fit: Generally favors people who expect their tax rate in retirement to be the same or higher than today — either because their income won't drop much, or because other income sources (Social Security, pensions, RMDs from traditional accounts) will keep their taxable income elevated.
Income limits: Roth IRAs have income eligibility limits. Above certain thresholds, direct contributions phase out. (Roth 401(k)s through employers don't have these limits.) If you're above the income limit, there are legal paths to a Roth IRA — the "backdoor Roth" conversion — but that's a decision worth reviewing with a tax professional.
Taxable accounts (no special treatment)
Example: Brokerage account.
No tax break going in, no special tax treatment coming out. You contribute after-tax dollars, and you pay capital gains tax on any growth when you sell. Dividends are also taxable each year.
Why they matter: No contribution limits. No withdrawal restrictions. You can take money out whenever you want, for any reason, without penalty. For money you might need before retirement or in amounts beyond IRS contribution limits, taxable accounts are the flexible overflow.
They also play a role in tax-efficient withdrawal strategies — but that's a decumulation-stage topic.
The employer match: the only guaranteed return
If your employer offers a 401(k) match — say, 50 cents per dollar up to 6% of your salary — contribute at least enough to capture it. Every dollar they add to your account is an immediate 50% or 100% return on your contribution, before any investment growth. There's nothing else in personal finance that works this well. Not capturing the full match is the clearest financial mistake most working people make.
Contribution limits and the order of operations
For 2026, annual contribution limits are:
- 401(k) / 403(b): $23,500 (plus $7,500 catch-up if you're 50 or older)
- IRA (traditional or Roth): $7,000 (plus $1,000 catch-up if you're 50 or older)
A common approach when you can't maximize everything:
- Contribute to your 401(k) up to the full employer match
- Max out a Roth IRA (if eligible — income limits apply)
- Return to the 401(k) and contribute more, up to the annual limit
- If you've maxed both and still have savings capacity, use a taxable brokerage account
This isn't a rigid rule — your tax situation, employer plan quality, and other goals all affect the ideal order. But as a starting framework it holds for most situations.
How Roth and traditional accounts interact in retirement
Here's something that surprises many people: by the time you retire, having both traditional and Roth balances gives you a valuable planning tool.
Traditional withdrawals add to your taxable income. Roth withdrawals don't. That means in a given year, you can draw from traditional accounts up to the top of a lower tax bracket, then supplement with Roth withdrawals to cover additional needs — keeping your total tax bill lower than if you drew purely from one source.
This is why some people intentionally do Roth conversions in the years before retirement (or in early retirement, before Social Security and RMDs fully kick in): they pay tax on traditional funds at today's rates to build a Roth balance they can draw on tax-free later. That strategy is covered in more depth in the next guide.
What RMDs mean for account planning
Traditional accounts (401(k), traditional IRA) require minimum distributions starting at age 73. The IRS calculates a minimum you must withdraw each year based on your account balance and life expectancy tables.
Large traditional balances create large RMDs — and large RMDs are taxable income. If your RMDs push you into a higher tax bracket, or trigger larger Social Security taxes, or trip Medicare's income-based surcharges (IRMAA), the tax bite in retirement can be larger than you expected when you were deferring contributions.
This is why the Roth vs. traditional decision matters more than just the immediate tax deduction. The choice you make today accumulates quietly for decades and determines what your tax picture looks like at 73 and beyond.
Roth IRAs have no lifetime RMDs. The money stays yours to deploy or pass on.
Common mistakes
- Confusing the account with the investment. A "Roth IRA" is not an investment — it's an account that holds investments. If your Roth IRA is earning very little, the question to ask is what's inside it.
- Missing the employer match. This is the most common and most costly mistake. Capture the full match before directing money anywhere else.
- Treating the Roth/traditional choice as permanent. It isn't. You can hold both. You can convert traditional funds to Roth over time. The decision is revisable — especially in the years just before and after retirement.
- Ignoring the RMD math. People who max traditional accounts for decades sometimes arrive at 73 with very large required minimum distributions — more taxable income than they need or expected. Diversifying between Roth and traditional during accumulation gives you more flexibility later.
- Assuming all 401(k) plans are equally good. They're not. Some have high-fee investment options that erode your returns quietly over time. If your employer's plan has poor options, you may want to contribute only enough to capture the match, then direct additional savings to an IRA with better choices.
Keep learning →
Next in Accumulation: Roth vs. Traditional — the decision that compounds
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