What Is a Share (and How Many Should You Buy)?

So you’re a part-owner

Companies are split into millions (sometimes billions) of shares. When you buy one, you own one of those pieces. That makes you a part-owner, for real. If the company grows and becomes more valuable, your little piece becomes more valuable too. That’s how investors make money.

What the share price means

The share price is just what one share costs right now. It moves up and down constantly while the market is open, based on what people are willing to pay. If a stock is $50 a share, buying 3 shares costs you $150.

So how many should you buy?

There’s no magic number. Work it backwards instead: decide how much money you want to invest, then divide by the share price. Got $100 to invest and the stock is $25 a share? That’s 4 shares.

You don’t even need a whole share anymore

This is the part a lot of beginners don’t know. Many brokerages (including Fidelity, which is what I use) let you buy fractional shares, meaning you can put in $20 on a stock that costs $500 a share and own a sliver of it. You no longer need hundreds of dollars to start. You can start with whatever you’ve got.

A quick heads-up on fees

Don’t stress about fees eating your first buy. At big brokerages like Fidelity, buying a stock costs $0 — no commission. There’s a tiny government fee of a few cents, but it’s charged when you sell, not when you buy, and on a small trade it’s usually just pennies. At this size, fees basically don’t matter.

The rules I’d actually follow

Buying a share is the easy part. The mindset is what actually matters. Three things I stick to:

Don’t invest money you’ll need soon. The market climbs over time, but it also drops sometimes. Only put in money you can leave alone for a while.

Never let one stock take over. This is my personal rule: I don’t let any single stock be more than 25% of my whole portfolio. That way, if one company has a terrible year, it can’t wreck everything I’ve built. Spreading your money across several different companies (or using index funds) is called diversifying, and it’s one of the simplest ways to lower your risk.

Think years, not days. Stocks are not a get-rich-quick thing, and trying to flip them fast usually backfires, for two reasons. First, prices bounce around almost randomly in the short term, so quick trading is closer to gambling than investing. Second, taxes. When you sell a stock for a profit, you may owe capital gains tax — and here’s the key part: if you held the stock for one year or less, that profit gets taxed at the higher “short-term” rate. Hold it longer than a year, and it’s taxed at the lower “long-term” rate. The tax system literally rewards you for being patient. (If you’re on a youth account like mine, those taxes usually run through your parent’s return, so it’s worth asking them about.)

So buy good companies, spread your money out, hold them, and let time do the heavy lifting.

This post is for educational purposes only and isn’t financial advice. Always do your own research before investing.