How to start investing: a plan for your first $100 to $500 a month

You do not need a lot of money to start investing, but you do need an order. Putting your first $100 to $500 a month in the right place, in the right sequence, matters more than which fund you pick. This guide gives you that sequence, explains which account to open, and shows what steady monthly investing can grow into.

Before you invest: know your monthly number

Investing starts with a budget surplus. Work out what is left after essentials, debt minimums and a realistic amount for everything else, and pick a fixed number you can invest every month without dipping back into it. The 50/30/20 split is a quick way to find it. A smaller amount you never miss beats a bigger one you keep pausing.

The order of operations

Work down this list. Each step either protects you or gives you a better return than the next one.

1. A starter emergency fund. Keep at least one month of essential costs in an insured savings account before you invest anything. Without it, the first car repair goes on a credit card or forces you to sell investments at a bad moment. Then keep building toward a full emergency fund alongside the next steps.
2. Your employer's 401(k) match. Many employers match part of what you put into a 401(k), 403(b) or similar plan. The SEC calls this free money, and it is an instant return no investment can promise. Contribute at least enough to get the full match. Our 401(k) match guide shows how to work out that amount.
3. High-interest debt. The SEC notes that credit cards can charge 18% or more, and that hardly any investment earns enough to keep up with that. Paying off the card is a guaranteed, risk-free return at that rate. The SEC suggests applying the same thinking to other debt charging around 8% or more that has no tax advantage. Paying the highest rate first, while making minimums on the rest, is the cheapest way to do it.
4. An IRA. Once the match is captured and expensive debt is gone, open an individual retirement account. For 2026 you can put in up to $7,500 (plus $1,100 extra if you are 50 or older), which works out to $625 a month. Choose between Roth and traditional using our Roth vs traditional guide.
5. More in the 401(k). Beyond the match, the 2026 employee limit is $24,500, with an $8,000 catch-up from age 50, or $11,250 at ages 60 to 63.
6. A taxable brokerage account. For goals before retirement, or once the tax-advantaged accounts are full. No limits and no withdrawal rules, but no tax break either.

With $100 to $500 a month, most people spend years on steps 1 to 4. That is normal and fine.

Choosing an account

• 401(k) or 403(b): opened through your employer, funded by payroll deduction. The fund menu is fixed, and you may be placed in a target-date fund by default. Check its fee.
• IRA: you open it yourself at a brokerage and can hold almost any fund. Look for no account minimum, no account fees and a wide choice of low-cost index funds.
• Taxable brokerage account: same providers, same funds, fewer rules. Dividends and gains are taxed each year you receive or realize them.

For what to buy inside the account, start with our guide to index funds and ETFs. One or two broad, low-cost funds are enough for a beginner.

Automate it

The SEC's roadmap recommends "paying yourself first": an automatic transfer from each paycheck into savings or investments, so the decision is made once. Set the transfer for the day after payday, and set the account to buy your chosen fund automatically.

One common slip: money arrives in an IRA or brokerage account and sits there as cash because nobody told it what to buy. After the first transfer, log in and check that the money was actually invested.

Dollar-cost averaging, honestly

Dollar-cost averaging means investing a fixed amount on a fixed schedule whatever the market is doing. The same $200 buys more fund shares when prices are low and fewer when they are high. If you invest from each paycheck, you are already doing this, and it is the right approach: you invest money as you earn it.

The question is different when you already have a lump sum, such as a bonus or an inheritance. Vanguard research published in 2023 compared investing a lump sum at once with spreading it over three months, using market data from the US, UK, Canada, Europe, Australia and emerging markets. Investing at once came out ahead in roughly 62% to 74% of rolling one-year periods, depending on the market, mainly because markets have risen more often than they have fallen. Spreading the money in did better in the worst periods, though.

So spreading a lump sum is mostly about limiting regret, not about earning more. If a short, fixed schedule is what gets you to invest at all, that is a reasonable trade.

What to avoid

• Stock tips. The SEC warns that social media promoters pump up small stocks and sell into the rise, and that hacked or fake accounts make tips look credible. Unsolicited tips, "inside information", guaranteed returns and pressure to act fast are all red flags. Check that anyone selling you an investment is registered before you pay.
• Leverage. Borrowing to invest, for example on margin, magnifies losses. FINRA's required margin disclosure is blunt: you can lose more than you deposit, and your broker can sell your holdings without contacting you.
• Frequent trading. Each trade can carry spreads, fees and, in a taxable account, a tax bill on short-term gains. Checking your balance daily mostly creates reasons to trade.

Worked example: $200 a month

Assumptions for illustration only: $200 invested automatically at the end of every month, a steady 6% annual return compounded monthly, no fees or taxes. Real returns vary and some years are negative. The SEC's roadmap puts long-run stock returns at around 10% a year before inflation, but notes that someone who invested at the 1929 peak waited more than 20 years to break even.

In the first decade, growth adds $8,776 to $24,000 of savings. By year 30, growth is 64% of the balance. The last ten years add more than the first twenty, which is why starting early with a small amount beats waiting until you can invest more. Try your own numbers in our compound growth calculator.

What to do this week

1. Pick your monthly investing number from your budget and write it down.
2. Check your employer plan's match formula and raise your 401(k) contribution to at least the full match.
3. If the match is covered and you have no high-interest debt, open an IRA and set up an automatic monthly contribution and an automatic fund purchase.
4. A week later, log in and confirm the money was invested, not left as cash.

General education, not personal financial advice. Figures are illustrations computed from the stated assumptions.