401(k) & Roth IRA Retirement Simulator

Q: What are the 2025/2026 IRS contribution limits for 401(k) and Roth IRA accounts?

For a 401(k), 403(b), or most 457 plans, the annual elective deferral limit is $23,000, plus an additional $7,500 catch-up contribution for individuals aged 50 and older (with higher catch-up limits for ages 60-63 under the SECURE 2.0 Act). For Traditional and Roth IRAs, the annual baseline limit is $7,000, with a $1,000 catch-up allowance for individuals 50 and older.

Q: How do I decide between a Traditional 401(k) and a Roth 401(k) or Roth IRA?

The decision depends primarily on comparing your current marginal income tax bracket against your expected effective tax bracket in retirement. If you are currently in a high tax bracket (24% to 37%), a Traditional 401(k) offers immediate upfront tax deductions. If you are early in your career or anticipate higher tax rates later, a Roth provides tax-free compound growth and completely tax-free withdrawals.

Q: How does an employer 401(k) match work?

A common employer match formula is 50% of your contributions up to 6% of your salary. If you earn $80,000 and contribute 6% ($4,800), your employer contributes an additional 3% ($2,400) directly into your account. This represents an instant, risk-free 50% return on invested capital.

Q: What is the 4% Safe Withdrawal Rule in retirement planning?

The 4% Rule, derived from the landmark Trinity Study, suggests that a retiree can safely withdraw 4% of their initial portfolio balance in the first year of retirement, adjusting subsequent annual withdrawals for inflation, with a high historical probability of not depleting funds over a 30-year retirement horizon.

Q: What happens to employer match money if I choose a Roth 401(k)?

Historically, all employer matching funds were required by the IRS to be placed into a pre-tax traditional account, meaning match withdrawals are taxed as ordinary income upon retirement. Under recent SECURE 2.0 Act revisions, employers may optionally offer designated Roth matching, though employees must pay taxes on that match in the tax year it is granted.

Q: What is the penalty for withdrawing funds before age 59½?

Early withdrawals from a Traditional 401(k) or IRA prior to age 59½ generally incur a 10% IRS early distribution penalty in addition to ordinary federal and state income taxes, unless an exception applies (e.g., Rule of 55 for 401k, qualified first-time home purchase for IRA, disability, or SEPP distributions under Section 72(t)).

Traditional vs. Roth Retirement Accounts: Strategic Tax Arbitrage

When planning for retirement in the United States, your primary structural decision is allocating savings between Traditional (pre-tax) and Roth (after-tax) accounts. Both frameworks offer formidable tax protections against annual capital gains and dividend taxes, but their timing mechanisms are opposite:

Traditional 401(k) & Traditional IRA: Contributions are deducted from your current gross income, reducing your federal and state tax liability in the contribution year. Your money compounds tax-deferred until retirement, at which point all withdrawals are taxed as ordinary earned income.
Roth 401(k) & Roth IRA: Contributions are made with after-tax dollars (providing no immediate tax break). However, all investment growth and qualified distributions taken after age 59½ are 100% tax-free forever.

The mathematical formula for comparing both options hinges on your marginal tax rate today ($T_0$) versus your effective tax rate in retirement ($T_1$). If $T_0 > T_1$, Traditional mathematically yields higher net purchasing power. If $T_0 < T_1$, Roth is vastly superior.

The Employer Match: An Unbeatable 100% Guaranteed Return

Personal finance experts universally agree on the primary rule of wealth accumulation: always contribute at least enough to capture your full employer 401(k) match.

If your employer offers a dollar-for-dollar match up to 4% of your salary, contributing 4% produces an instantaneous, guaranteed 100% return on your money before your investments even begin compounding in the stock market. No hedge fund, venture capital firm, or speculative asset class can consistently match this risk-free return. Failing to capture this match is equivalent to refusing earned compensation from your employer.

The Compounding Curve: The Cost of Delaying by 10 Years

Albert Einstein famously called compound interest the eighth wonder of the world. In retirement planning, time is significantly more potent than the nominal amount contributed. The reference table below examines what happens when an investor saves $500 per month ($6,000 annually) at an 8.0% average annual return starting at different ages until age 65:

Starting Age	Years Investing	Total Out-of-Pocket	Compound Growth	Portfolio at Age 65
Age 25	40 Years	$240,000	$1,555,274	$1,795,274
Age 35	30 Years	$180,000	$640,084	$820,084
Age 45	20 Years	$120,000	$224,204	$344,204
Age 55	10 Years	$60,000	$49,694	$109,694

Notice that the investor who begins at age 25 accumulates nearly $1 million more than the investor who delays until age 35, despite contributing only $60,000 more in total principal over their career.

The 4% Safe Withdrawal Framework

Upon reaching retirement, how much can you safely draw down each year without depleting your principal over a 30-year span? Under the widely referenced 4% Safe Withdrawal Rule, an ending balance of $1,500,000 supports an initial annual retirement income of $60,000 ($5,000 per month), adjusted annually for inflation. When combined with projected Social Security benefits, this structure provides a durable income stream for lifelong security.

Frequently Asked Questions (US Standards)

What are the 2025/2026 IRS contribution limits for 401(k) and Roth IRA accounts?

For a 401(k), 403(b), or most 457 plans, the annual elective deferral limit is $23,000, plus an additional $7,500 catch-up contribution for individuals aged 50 and older (with higher catch-up limits for ages 60-63 under the SECURE 2.0 Act). For Traditional and Roth IRAs, the annual baseline limit is $7,000, with a $1,000 catch-up allowance for individuals 50 and older.

How do I decide between a Traditional 401(k) and a Roth 401(k) or Roth IRA?

The decision depends primarily on comparing your current marginal income tax bracket against your expected effective tax bracket in retirement. If you are currently in a high tax bracket (24% to 37%), a Traditional 401(k) offers immediate upfront tax deductions. If you are early in your career or anticipate higher tax rates later, a Roth provides tax-free compound growth and completely tax-free withdrawals.

How does an employer 401(k) match work?

A common employer match formula is 50% of your contributions up to 6% of your salary. If you earn $80,000 and contribute 6% ($4,800), your employer contributes an additional 3% ($2,400) directly into your account. This represents an instant, risk-free 50% return on invested capital.

What is the 4% Safe Withdrawal Rule in retirement planning?

The 4% Rule, derived from the landmark Trinity Study, suggests that a retiree can safely withdraw 4% of their initial portfolio balance in the first year of retirement, adjusting subsequent annual withdrawals for inflation, with a high historical probability of not depleting funds over a 30-year retirement horizon.

What happens to employer match money if I choose a Roth 401(k)?