How Much Money Do You Need to Start Investing?
The real answer is less than you think. Here is a breakdown by situation, from $1 starter buys to ideal monthly targets.
Don't have time? Here's what you need to know:
- 1You can technically start with $1 through fractional shares, but aim for at least $50-100 per month
- 2$200 a month for 30 years at 10% returns grows to nearly $395,000
- 3Pay off high-interest debt first, but do not wait to be debt-free to start investing
- 4Starting with $100 today beats planning to start with $500 'someday'
The Technical Minimum: $1
Fidelity lets you buy $1 worth of any ETF through fractional shares. Robinhood and SoFi have the same $1 minimum. Schwab requires $5 for fractional ETF purchases. The technical barrier to entry has never been lower. You can own a piece of the S&P 500 for the price of a candy bar.
But the technical minimum and the practical minimum are different questions. One dollar invested once will not change your financial future. The question that matters is: how much should you invest regularly to make a meaningful difference over 10-30 years?
What Different Monthly Amounts Actually Produce
Here is what consistent monthly investing in a broad stock market ETF grows to, assuming the historical average return of about 10% per year. These numbers assume you start from zero and invest the same amount every month for the full period.
The pattern is clear: doubling your monthly amount doubles your ending balance. But doubling your time horizon more than doubles it, thanks to compounding. $200 a month for 30 years beats $400 a month for 20 years by over $100,000.
| Monthly Amount | After 10 Years | After 20 Years | After 30 Years |
|---|---|---|---|
| $50 | $9,600 | $34,400 | $98,700 |
| $100 | $19,200 | $68,700 | $197,400 |
| $200 | $38,300 | $137,500 | $394,800 |
| $500 | $95,800 | $343,700 | $987,000 |
| $1,000 | $191,600 | $687,400 | $1,974,000 |
Rules of Thumb by Income Level
A common guideline is to invest 15-20% of your gross income for retirement. If you earn $50,000, that is $625-$833 per month. If you are in your 20s and that feels aggressive, start with 10% and increase by 1% every time you get a raise. The worst starting amount is $0.
Before investing, make sure you have a 3-month emergency fund in a high-yield savings account and no high-interest debt (credit cards at 20%+ APR). Paying off a 22% credit card is a guaranteed 22% return — better than any ETF. Student loans at 4-6% are lower priority; you can invest and pay those off simultaneously.
Tip: Use the 50/30/20 budget as a starting point: 50% needs, 30% wants, 20% savings and investing. Adjust the 30% category first when you want to invest more.
Ready to invest? Open an IBKR account in 10 minutes and get free stock. $0 commissions on US ETFs • Fractional shares from $1 • 150+ global markets.
The Best Strategy: Start Small, Increase Over Time
If $500 a month feels like too much right now, start with $100. The habit of investing matters more than the amount. Every January or every time you get a raise, bump it up by $25-50. A 25-year-old who starts at $100 and adds $25 per month each year invests $100 in year one, $400 in year two, $700 in year three — and builds a much larger portfolio than someone who plans to start investing $500 a month 'someday' but never does.
The math of delay is brutal. A 25-year-old investing $300 a month until age 65 accumulates roughly $1.58 million (at 10%). A 35-year-old investing the same $300 a month until 65 accumulates about $592,000. Those 10 extra years of compounding are worth nearly a million dollars.
Frequently Asked Questions
Is $100 a month enough to build real wealth?
Yes. $100 per month invested in a broad stock market ETF at the historical 10% average return grows to roughly $197,000 after 30 years. That is on total contributions of just $36,000. The other $161,000 is pure compound growth. Consistency over decades is what builds wealth, not the starting amount.
Should I save up a lump sum or invest small amounts monthly?
Invest monthly. Studies show that lump-sum investing beats dollar-cost averaging about two-thirds of the time, but most people do not have lump sums sitting around. If you wait to save up $5,000, you lose months of market exposure. Start with what you have now and add to it every month.
Should I pay off all debt before investing?
Pay off high-interest debt (credit cards, payday loans) first — guaranteed 20%+ return. For lower-interest debt like student loans (4-6%), you can invest simultaneously. Always get your full 401(k) employer match regardless of debt — that is 50-100% instant return on your contribution.
Further Reading
Free Tools
Alex Harrington
CFA Level II Candidate, Finance & Economics
Alex Harrington is an independent ETF researcher and personal finance writer with over 8 years of experience analyzing exchange-traded funds. A CFA Level II candidate with a background in economics, Alex has reviewed 800+ ETFs and helped thousands of beginners build their first investment portfolios through clear, jargon-free education.
This content is for educational purposes only and does not constitute financial advice. Past performance does not guarantee future results. Consult a licensed financial advisor before making investment decisions.