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401(k) Growth From Age 40 to 55

Based on default salary and contribution assumptions. Use the calculator below to adjust any input.

Your age today. Used together with retirement age to determine how many years your 401(k) has to grow.
The age you plan to stop contributing and start withdrawing from your 401(k).
How much you already have saved in your 401(k) today.
$
Your current gross annual salary, used to compute contribution amounts as a percentage of pay.
$
The percentage of your salary you contribute to your 401(k) each pay period.
%
How much of your contribution your employer matches, e.g. 50% means they add 50 cents per dollar you contribute.
%
The maximum share of your salary your employer will match contributions on, regardless of how much more you contribute.
%
The average annual raise you expect, which grows both your salary and dollar contributions over time.
%
The average annual investment return you expect on your 401(k) balance, before retirement.
%
The IRS cap on employee elective deferrals per year. Defaults to the 2025 limit of $23,500 — adjust if a different year's limit applies.
$

Projected Balance at Age 55

Example

Starting at age 40 with $20,000 saved and contributing 6% of a $65,000 salary, with a 50% employer match up to 6% of pay, your 401(k) could grow to approximately $232,095 by age 55 — $67,444 from your own contributions, $33,722 from employer match, and $110,928 from investment growth.

Your Contributions

$67,444

Employer Match

$33,722

Investment Growth

$110,928

Years to Grow

15 yrs

Balance at retirement, split by source

  • Your Contributions: $67,444
  • Employer Match: $33,722
  • Investment Growth: $110,928

What is a 401(k)?

A 401(k) is an employer-sponsored retirement savings plan in the United States that lets employees contribute a portion of their pre-tax (or Roth after-tax) salary into an investment account. Many employers add a matching contribution on top of what the employee puts in, effectively acting as free money toward retirement — up to a limit tied to the employee's own contribution rate.

Money inside a 401(k) grows tax-deferred (or tax-free for Roth accounts) until withdrawal, and the combination of regular contributions, employer match, and compounding investment returns over a multi-decade career is usually the single largest driver of retirement savings for most workers.

Balance growth by age

Year-by-Year Balance Schedule
Age Your Contributions Employer Match Balance
40 $0 $0 $20,000
41 $3,900 $1,950 $27,660
42 $7,878 $3,939 $35,980
43 $11,936 $5,968 $45,011
44 $16,074 $8,037 $54,805
45 $20,296 $10,148 $65,417
46 $24,602 $12,301 $76,907
47 $28,994 $14,497 $89,339
48 $33,474 $16,737 $102,783
49 $38,043 $19,022 $117,312
50 $42,704 $21,352 $133,005
51 $47,458 $23,729 $149,945
52 $52,307 $26,154 $168,225
53 $57,253 $28,627 $187,939
54 $62,298 $31,149 $209,192
55 $67,444 $33,722 $232,095

How Is 401(k) Growth Calculated?

Each year, your contribution (a percentage of salary, capped at the IRS annual limit) and your employer's match (a percentage of your contribution, up to a limit tied to your salary) are added to your balance, which then grows at your expected annual investment return. Salary is assumed to increase every year by your expected raise percentage, which grows dollar contributions over time even if your contribution rate stays flat.

Balance = (Balance + Employee Contribution + Employer Match) × (1 + Return Rate)

Why the Employer Match Matters So Much

An employer match is an immediate, guaranteed return on your contribution before any investment growth even happens — a 50% match is equivalent to an instant 50% return on the matched dollars. Contributing less than what's needed to capture the full match effectively leaves free money on the table, which is why most financial advisors recommend contributing at least enough to max out the match before directing savings elsewhere.

Contribution Limits Change Almost Every Year

The IRS adjusts the annual employee elective deferral limit for inflation most years — this calculator defaults to the 2025 limit of $23,500, but you can edit the field to match the current year's limit or model a scenario with catch-up contributions if you're 50 or older.

Small Rate Differences Compound Dramatically

Because a 401(k) balance compounds annually over potentially 30-40 years, small differences in contribution rate or expected return produce outsized differences in the final balance. Raising your contribution rate by even 1-2% early in a career, or choosing investments with a meaningfully higher expected return, tends to matter far more than trying to time contributions perfectly.

Example — Your Current Inputs

Starting at age 40 with $20,000 saved and contributing 6% of a $65,000 salary, with a 50% employer match up to 6% of pay, your 401(k) could grow to approximately $232,095 by age 55 — $67,444 from your own contributions, $33,722 from employer match, and $110,928 from investment growth.

Additional Example — Starting at 25

A 25-year-old earning $50,000, contributing 6% with a 50% employer match up to 6% of pay, and earning a 7% average annual return, would have roughly $580,000 saved by age 65 — even without any salary growth. Delaying the same plan by ten years, to start at age 35 instead, cuts the projected balance by nearly half, illustrating how much starting age affects the final result.

About These Parameters

Current Age & Retirement Age
These set the number of years your 401(k) has left to grow. Even a few extra years of contributions and compounding can meaningfully change the projected balance, especially earlier in a career.
Current Balance & Annual Salary
Your starting balance is grown alongside new contributions. Salary determines the dollar size of both your contribution and the employer match, since both are typically expressed as a percentage of pay.
Contribution Rate & Employer Match
Most employers match a percentage of what you contribute, up to a cap expressed as a percentage of salary — for example "50% match up to 6% of pay" means you must contribute at least 6% to receive the maximum match.
Salary Increase & Expected Return
Salary increase compounds your dollar contributions each year even at a flat contribution rate. Expected return should reflect your actual investment mix — stock- heavy portfolios have historically returned more on average, with more year-to-year volatility, than bond-heavy ones.

Frequently Asked Questions

How much should I contribute to my 401(k)?

At minimum, enough to capture the full employer match — anything less forgoes free money. Beyond that, many savers target 10-15% of pay including the match, though the right number depends on your other savings goals and the IRS annual contribution limit.

Does the employer match count toward the IRS limit?

No — the employee elective deferral limit ($23,500 for 2025) applies only to what you personally contribute. Employer contributions fall under a separate, much higher combined limit that rarely affects typical savers.

Is this projection guaranteed?

No — this is an estimate based on a constant assumed annual return, which real investments never deliver exactly. Actual returns vary year to year, and this calculator does not account for taxes on withdrawal, fees, or changes to contribution limits over multi-decade periods.

Other Retirement Ages Starting at 40

Other Starting Ages Retiring at 55

See also