compare_arrowsStrategy Comparison

Coast FIRE: 401k vs Taxable Brokerage — Which Account to Use?

Reference FIRE Number

$1.5M

Target Age

65

Monthly Needed

$600

The account type matters significantly for Coast FIRE strategy, particularly during the "coast phase" (ages 40–65 for an early coaster) when the portfolio is growing but not being drawn down. All invested assets — 401k, IRA, and taxable brokerage — count toward the coast number. But the optimal allocation between tax-advantaged and taxable accounts affects tax efficiency during both accumulation and the coast phase itself.

401k advantages for Coast FIRE: pre-tax contributions reduce current taxable income (saving 22–37% in federal taxes on every contributed dollar), employer matching is free money, and the tax-deferred growth means no annual tax drag on dividends or capital gains. Disadvantages: early withdrawal penalty before 59½ (though 72(t), Rule of 55, and Roth conversion ladders mitigate this), required minimum distributions at 73, and all withdrawals taxed as ordinary income.

Taxable brokerage advantages for Coast FIRE: no contribution limits, no withdrawal restrictions at any age, long-term capital gains taxed at 0–20% (vs. ordinary income rates for 401k withdrawals), and the ability to harvest tax losses to offset gains. Disadvantages: no tax deduction on contributions, dividends taxed annually, and no employer matching. For Coast FIRE practitioners who plan to retire before 59½, the taxable brokerage provides penalty-free access during the gap years.

The optimal account strategy for most Coast FIRE planners: (1) 401k contributions up to employer match — always, regardless of other account strategy; (2) Roth IRA ($7,000/year) — particularly valuable during the coast phase when income may be lower (ideal for Roth conversions at lower tax rates); (3) Max 401k to $23,500; (4) Taxable brokerage with any remaining savings. During the coast phase itself, the taxable brokerage provides the most flexible access — use it for expenses before 59½ while leaving 401k to compound.

Try It: Model This Scenario

Common Questions

Does account type affect the Coast FIRE number?expand_more
The coast number itself is the same regardless of account type — it's based on your total invested assets. But account type affects (1) how tax-efficiently you accumulate the coast number; (2) how you access the money during the coast phase (before 59½); and (3) your tax efficiency in retirement. Build your coast number in the most tax-efficient accounts available, then plan the access sequence carefully.
Should Coast FIRE assets be in a 401k or taxable account?expand_more
Both — in priority order: (1) 401k to employer match; (2) Roth IRA; (3) Max 401k; (4) Taxable brokerage. For the coast phase (before 59½), the taxable brokerage provides penalty-free access. Keep 3–7 years of coast-phase expenses in taxable accounts if you plan to retire the traditional savings grind before 59½. The 401k/IRA can compound undisturbed until 59½ or Roth conversion is complete.
What is the Roth conversion ladder and why does it matter for Coast FIRE?expand_more
The Roth conversion ladder converts traditional 401k/IRA funds to Roth IRA during low-income years (like the coast phase). After 5 years, converted amounts (not growth) are available penalty-free. Coast FIRE practitioners in their 40s and 50s with low-income coast jobs can convert $10K–$20K/year at low tax rates, building a Roth ladder for penalty-free retirement income. This is the primary strategy for accessing 401k funds before 59½.
What is the Rule of 55 and does it help Coast FIRE practitioners?expand_more
Rule of 55 allows distributions from your current employer's 401k without the 10% penalty if you leave that job in the year you turn 55 or later. For Coast FIRE practitioners who coast to age 55, this unlocks 401k access 4.5 years before the standard 59½ penalty-free age. This makes the 55-year coast date attractive for many people — the coast window ends and traditional retirement infrastructure begins simultaneously.
Should I include my Roth IRA contributions (not growth) in the coast number?expand_more
Yes — Roth IRA contributions (not growth) can be withdrawn penalty-free at any age. They count fully toward your coast number. Roth IRA growth cannot be accessed before 59½ without penalty (with some exceptions). When calculating your coast portfolio, include all Roth IRA balances — contributions are accessible, growth is a bonus that compounds until you can access it penalty-free.

More Comparisons

compare_arrowsCoast FIRE vs Regular FIREcompare_arrowsCoast Number vs FIRE Numbercompare_arrowsCoast FIRE at 45compare_arrowsFreelancer Coast FIREcalculateFull Calculator