The sequence matters more than the accounts
Most people know they should be using a 401k. Many know about Roth IRAs. Fewer know about HSAs. Almost nobody thinks carefully about which account to fill first, second, and third — and the order turns out to matter a lot.
The reason: different accounts have different tax treatments, and some come with employer contributions that are free money with a 100% instant return. Filling the wrong account first isn't a catastrophic mistake, but it's a consistent, compounding one. Over a 20-year career, the difference between an optimized sequence and a random one can exceed $40,000 in pure tax savings — before any return differences.
Here's the sequence that maximizes tax efficiency for most FIRE-focused earners.
Step 1: Capture the full employer match
If your employer offers a 401k match and you aren't contributing enough to capture all of it, everything else on this list is secondary. The match is a guaranteed 50–100% return on every dollar — it's not possible to beat it anywhere else.
A 50% match on the first 6% of salary at $100,000 income means: contribute $6,000, get $3,000 free. That's a 50% instant return before the first day of market returns. Even in a 9% HELOC or a 4% mortgage payoff scenario, nothing touches a dollar-for-dollar match.
Two nuances worth knowing:
Vesting schedules. Some matches vest immediately; others vest over 2–6 years. If you leave after one year at a company with a 3-year vesting cliff, you leave the match behind. Know your schedule.
True-up provisions. If you hit the annual 401k limit ($23,500 in 2026) mid-year and stop contributing, some employers stop matching too — even if you'd have gotten more match had you spread contributions evenly. Check whether your plan does a year-end true-up.
Step 2: Max the HSA (if you have a qualifying health plan)
The Health Savings Account is the most tax-efficient investment account in the U.S. tax code — and most people treat it as a medical spending account. That's a mistake.
An HSA is triple tax-advantaged:
- Contributions are pre-tax — you reduce your taxable income dollar for dollar (and if contributed via payroll, you avoid FICA too, which no other pre-tax account can claim)
- Growth is tax-free — invest it in index funds and it compounds with no annual tax drag
- Withdrawals for qualified medical expenses are tax-free — at any age
The fourth fact that most people miss: after age 65, the funds can be withdrawn for any purpose and are taxed like a Traditional IRA distribution. The medical restriction disappears. This makes an invested HSA a fully functional retirement account with better tax treatment than a 401k on the way in (because of the FICA exemption).
The 2026 contribution limits: $4,300 for self-only coverage, $8,550 for family coverage.
The FIRE strategy: pay current medical expenses out of pocket (if you can), keep the receipts, let the HSA invest and compound for decades, and reimburse yourself in retirement — tax-free — for every out-of-pocket medical dollar you've ever spent. There's no statute of limitations on HSA reimbursements if the expense occurred after you opened the account.
The caveat: you must be enrolled in a High-Deductible Health Plan (HDHP) to contribute. In 2026, that means a plan with a deductible of at least $1,650 (self-only) or $3,300 (family). If you're on an employer plan with a low deductible, you can't use an HSA that year.
Step 3: Contribute to an IRA — Roth or Traditional?
With the match captured and the HSA funded, the next stop is an individual retirement account. The 2026 limit is $7,000 ($8,000 if you're 50 or older). The choice between Roth and Traditional is the hinge decision.
The framework is simple: contribute Roth when you expect your tax rate in retirement to be higher than your current marginal rate; contribute Traditional when you expect it to be lower.
The FIRE-community translation:
- If you're early career with low income — probably Roth. Your current marginal rate (say 12% or 22%) is likely below what you'll face in retirement when Social Security, RMDs, and investment income stack up.
- If you're in peak earning years — probably Traditional. A 24% or 32% deduction now may well exceed the tax you'll pay on those same dollars at a lower rate in early retirement, especially if you're withdrawing $60,000/year from a paid-off-house lifestyle.
- If you're in the 22% bracket and genuinely uncertain — either is fine. The Roth's tax-free growth is valuable; the Traditional's immediate deduction is also valuable. Don't let the uncertainty paralyze the decision.
The income limit trap. Roth IRA contributions phase out for single filers between roughly $150,000 and $165,000 of modified adjusted gross income in 2026, and for married filers between $236,000 and $246,000. Above those thresholds, direct Roth contributions aren't allowed — but the backdoor Roth (contribute to a non-deductible Traditional IRA, then convert it) is available to most people. If you have no existing Traditional IRA balance, the backdoor is clean. If you have a large Traditional IRA from old 401k rollovers, the pro-rata rule complicates it.
The Traditional IRA deduction phases out at lower thresholds if you have access to a 401k at work: roughly $81,000–$91,000 for single filers in 2026. Above that, Traditional IRA contributions are still allowed but are non-deductible — which is almost always worse than Roth.
Step 4: Fill the rest of the 401k
After the IRA, go back to the 401k and max it out. The 2026 employee contribution limit is $23,500. You've already contributed enough to capture the match (Step 1). Now you're filling the remaining capacity.
At this step the Roth vs. Traditional question applies here too — most employers now offer a Roth 401k option. Same logic: if you expect your retirement rate to be higher, use the Roth 401k; if lower, use Traditional pre-tax.
One tax planning angle worth noting: in high-income years, maxing the pre-tax 401k reduces your MAGI, which can affect whether you qualify for a Roth IRA directly (rather than via backdoor), the size of the Traditional IRA phaseout, and even ACA premium tax credits if you're managing income in early retirement.
The math on a $23,500 contribution in the 24% bracket: you defer roughly $5,640 in federal income tax immediately. That $5,640 stays in your account, compounds, and you pay tax on it later — hopefully at a lower rate.
Step 5: Taxable brokerage
Once all tax-advantaged space is filled, the taxable brokerage account isn't a consolation prize. It has meaningful advantages:
- No contribution limit — invest whatever you can
- No withdrawal restrictions — the FIRE community lives here for early retirement, because most tax-advantaged accounts carry penalties for pre-59½ withdrawals (with specific exceptions)
- Favorable long-term capital gains rates — 0%, 15%, or 20%, depending on income. Far below ordinary income tax rates for most people.
- Tax-loss harvesting — a real edge in down years that isn't available in tax-advantaged accounts
Index ETFs in a taxable account are also extremely tax-efficient — they rarely distribute capital gains, so most of the return comes as unrealized appreciation you control the timing of.
The main downside: dividends are taxable in the year they're paid. For FIRE folks targeting income independence, that dividend tax drag is why many prefer total-market funds (lower yield) over dividend-focused strategies in taxable accounts.
A worked example
Scenario: $120,000 salary, 24% federal marginal bracket, employer offers 50% match on first 6%, HDHP-eligible, single filer.
| Step | Account | Amount | Immediate tax saving |
|------|---------|--------|---------------------|
| 1 | 401k (to match) | $7,200 | $1,728 federal + $551 FICA |
| 2 | HSA | $4,300 | $1,032 federal + $329 FICA |
| 3 | Traditional IRA | $7,000 | $1,680 federal |
| 4 | 401k (remaining) | $16,300 | $3,912 federal |
| 5 | Taxable | whatever remains | — |
Total pre-tax contributions in Steps 1–4: $34,800. Federal tax deferred this year: roughly $8,352. FICA saved on Steps 1–2 payroll contributions: approximately $880. Total tax not paid this year: around $9,200.
Over 20 years at 8% returns, that $9,200 annual tax deferral (reinvested) compounds to roughly $430,000 in additional portfolio value — from the sequencing alone, not from working harder or earning more.
Your marginal rate is the key input
Every decision in this sequence — Roth vs. Traditional, how much Traditional IRA makes sense, whether pre-tax 401k beats Roth 401k — turns on one number: your current marginal federal rate versus your expected marginal rate in retirement.
The Tax Bracket Calculator on STWLTH shows you exactly where you sit today: your marginal rate, your effective rate, and how each pre-tax slider (401k, HSA, Traditional IRA) changes both. Move the 401k slider and watch your taxable income drop in real time. See which bracket each dollar falls into. Compare "current year with max contributions" against "current year without them."
That comparison card is the clearest way to see what this sequencing is actually worth in your specific numbers — not a generic example, your numbers.
*Contribution limits from IRS Notice 2025-71 (401k), Rev. Proc. 2025-19 (HSA), and IRS Rev. Proc. 2025-32 (IRA/MAGI thresholds). Confirm current-year limits at irs.gov. This article is not financial advice.*