How Much Should You Save Per Month for Retirement?

How much should you save per month for retirement? It is one of the most Googled personal finance questions — and the answers range from vague rules of thumb to paralyzing complexity. The honest answer is that it depends on three things: how much you will need, when you want to retire, and what you have saved already. This guide works through the math step by step, from figuring out your target number all the way back to the monthly savings amount you actually need to hit it.

Start with the target: how much do you need to retire?

Before you can calculate a monthly savings number, you need a retirement savings goal. The most widely used benchmark is the 25x rule, which comes from the 4% safe withdrawal rate: if you withdraw 4% of your portfolio in year one and adjust for inflation each year after, historical data suggests your money will last at least 30 years.

To use it, estimate your annual spending in retirement and multiply by 25:

• Annual spending of $50,000 → target: $1,250,000
• Annual spending of $70,000 → target: $1,750,000
• Annual spending of $90,000 → target: $2,250,000

Two important adjustments: Social Security benefits reduce how much your portfolio needs to cover, and any pension or part-time income in retirement does the same. If you expect $24,000 per year from Social Security, that effectively reduces your required portfolio by $600,000 (24,000 × 25).

Use DigiCalc's retirement calculator to project your savings growth toward a specific goal, factoring in your current balance, monthly contributions, and expected return.

Work backwards to your monthly savings number

Once you have a target, the monthly savings amount depends on three variables: how much you have saved today, how many years you have until retirement, and your expected investment return. The math is driven by compound interest — your money grows not just on what you contribute, but on what it has already earned.

Example: starting at 30 with nothing saved

Goal: $1,500,000 by age 65 (35 years)
Assumed return: 7% per year (a common long-run stock market estimate after inflation)
Current savings: $0

To reach $1,500,000 in 35 years at 7% annual growth, you need to save approximately $930 per month. That monthly contribution, compounded over 35 years, turns into $1.5 million — even though you only contributed about $390,000 out of pocket. The remaining $1.1 million came from compound growth.

Example: starting at 40 with $50,000 saved

Goal: $1,500,000 by age 65 (25 years)
Assumed return: 7% per year
Current savings: $50,000

Your $50,000 already saved grows to roughly $271,000 over 25 years at 7%. That means you need your monthly contributions to cover the remaining $1,229,000. At 7% over 25 years, that requires about $1,540 per month — roughly 65% more than the 30-year-old example, despite only a 10-year head start difference. This is why starting earlier matters so much: you are buying time, and time is the engine of compounding.

The 15% rule: the shortcut benchmark

Running the full backward calculation is the most accurate approach, but most people want a quick gut-check first. The standard rule of thumb from financial planners is: save 15% of your gross income for retirement, including any employer match.

On a $70,000 salary, 15% equals $10,500 per year, or $875 per month. If your employer matches 4% of your salary ($2,800 per year), you only need to contribute 11% yourself — about $642 per month — to hit the combined 15% target.

The 15% rule assumes you start by your mid-20s and retire around 65. If you started later, the percentage needs to go up:

• Start at 25: 15% of income is generally enough
• Start at 35: aim for 18–20%
• Start at 45: aim for 25–30%
• Start at 55: maximize every available account and consider delaying retirement

How compound interest makes your early contributions so powerful

The single most important insight in retirement saving is that a dollar saved at 25 is worth dramatically more than a dollar saved at 45, because it has 20 more years to compound. Consider two savers:

• Early Elena saves $500/month from age 25 to 35 (10 years, $60,000 contributed), then stops contributing entirely. At 7% annual return, she has roughly $1,067,000 at age 65.
• Late Larry saves $500/month from age 35 to 65 (30 years, $180,000 contributed). At 7% annual return, he has roughly $567,000 at age 65.

Elena contributed one-third as much as Larry but ends up with nearly twice as much, simply because her money had more time to grow. This is the compounding effect in its starkest form.

You can model exactly how your money grows over time with DigiCalc's compound interest calculator — try different monthly contribution amounts and time horizons to see the long-run difference a few extra years (or a few extra dollars per month) makes.

Retirement account types and contribution limits

Where you save matters almost as much as how much you save, because taxes dramatically affect your long-run outcome.

401(k) and 403(b)

Employer-sponsored plans are the backbone of retirement saving for most workers. In 2025, you can contribute up to $23,500 per year to a 401(k) or 403(b). Workers aged 50 and older can add a catch-up contribution of $7,500, bringing the limit to $31,000. Traditional contributions are pre-tax, reducing your taxable income today. Roth contributions go in after-tax but grow and come out tax-free.

IRA (Individual Retirement Account)

IRAs supplement employer plans and are available to anyone with earned income. The 2025 contribution limit is $7,000 per year ($8,000 if you are 50 or older). Traditional IRAs may be tax-deductible depending on your income and whether you have a workplace plan. Roth IRAs grow tax-free, but income limits apply — single filers earning above $161,000 and married filers above $240,000 begin to phase out of Roth eligibility in 2025.

HSA (Health Savings Account)

If you have a high-deductible health plan, an HSA is an underused retirement savings vehicle. Contributions are pre-tax, growth is tax-free, and withdrawals for qualified medical expenses are tax-free — a triple tax advantage. After age 65, you can withdraw for any purpose (just paying ordinary income tax, like a traditional IRA). The 2025 limit is $4,300 for individuals and $8,550 for families.

Age-based savings benchmarks

If the math feels abstract, these checkpoints — popularized by Fidelity — give you a rough calibration based on your current salary:

• By age 30: 1× your annual salary saved
• By age 40: 3× your annual salary saved
• By age 50: 6× your annual salary saved
• By age 60: 8× your annual salary saved
• By retirement (67): 10× your annual salary saved

These are rough guides, not guarantees. Someone who plans to live more modestly in retirement or expects significant Social Security income may need less. Someone who retires early or has higher spending expectations needs more. Use the checkpoints to spot if you are significantly off track, then run the full projection to understand how much to adjust.

What to do if you are behind

Most people are behind on retirement savings — and catching up is absolutely possible. Here are the highest-leverage moves:

• Get the full employer match first. An employer match is an instant 50–100% return on your contribution. If you are not contributing at least enough to capture the full match, fix that before anything else.
• Increase contributions with every raise. Each time your income goes up, direct half the increase to retirement savings. You will not miss money you never got used to spending.
• Max catch-up contributions at 50. The additional $7,500 in a 401(k) and $1,000 in an IRA add up to $8,500 per year of extra savings — more than $700 per month.
• Cut one expense that you will not miss. Redirecting $200–$300 per month from a subscription, dining budget, or recurring expense into a retirement account over 20 years at 7% produces more than $130,000 in additional savings.
• Delay retirement by a few years if possible. Each year you wait has a double effect: one more year of contributions and one fewer year of withdrawals. Working until 67 instead of 65 can meaningfully change whether your money lasts.

For a complete picture of whether your current savings rate will get you to your goal, run your numbers through DigiCalc's retirement calculator. You can adjust your target retirement age, expected return, and monthly contribution to find the combination that works for your situation. See also our deep dive on whether the 4% rule still holds — it covers the research behind the withdrawal rate that underpins most retirement savings targets.

Saving for retirement is not about hitting a perfect number — it is about building a habit, starting as early as you can, and adjusting over time as your income and goals change. Even a small increase in monthly savings, sustained over decades, compounds into a meaningfully different retirement. The best move you can make today is to calculate your specific target and close the gap between where you are and where you need to be.