How do I start investing with $100?
In one paragraph
Open a Roth IRA or taxable brokerage account at Fidelity, Schwab, or Vanguard — all have no minimums — and buy a single low-cost total market index ETF or mutual fund with the full $100.
What this actually means
The barrier to starting with $100 is almost entirely psychological, not practical. The mechanics are straightforward, and the platforms that make it easiest are also the ones with the lowest costs.
The first decision is account type. If earned income is available, a Roth IRA is the highest-priority first account. Contributions grow tax-free and can be withdrawn without penalty in retirement. The 2024 annual limit is $7,000 — well above the $100 starting point. A taxable brokerage account is the alternative for investors who have already maxed tax-advantaged accounts or who need potential access to the funds before retirement age.
The second decision is platform. Fidelity and Schwab both offer accounts with no minimums, no account fees, and fractional share trading — meaning a $100 investor can buy a partial share of any ETF without needing to meet a per-share price. Vanguard has historically required higher minimums for some funds but has reduced them significantly and also offers ETF access with no minimum.
The third decision is what to buy. For a $100 starting investment, simplicity wins. A single total U.S. stock market index fund (like FXAIX at Fidelity, SWTSX at Schwab, or VTI at Vanguard) provides exposure to thousands of companies at an expense ratio near zero. The investor owns a slice of the entire U.S. economy with one purchase.
What matters more than the initial $100 is the habit it establishes. Automating a recurring contribution — even $25 or $50 per month — turns a single starting investment into a compounding machine over time. Dollar-cost averaging, the practice of investing fixed amounts at regular intervals regardless of market conditions, removes the timing decision and accumulates shares at average prices over market cycles.
JL Collins's The Simple Path to Wealth makes the practical case for exactly this approach in accessible terms. Your Money or Your Life by Vicki Robin frames the decision to invest in terms of life energy — each dollar saved and invested represents hours that no longer need to be traded for a paycheck — which is particularly motivating for investors starting with small amounts.