How the Stock Market Works: A Canadian Investor’s Guide
The stock market is a second-hand market for ownership. That is the entire idea, and almost everything confusing about it follows from people not being told the second-hand part. Shares already exist. They are already owned by somebody. When you buy one, you are not funding a company, you are taking a slice of ownership off the hands of the person who held it before you, at a price the two of you happen to agree on at that instant.
Understanding how the stock market works means understanding four things: where the shares came from, how a buyer and a seller find each other, who is standing in the middle when they cannot, and what happens in the hours and days after you click buy. This guide walks through all four using Canada’s actual market structure: the Toronto Stock Exchange, the TSX Venture Exchange, the trading sessions those exchanges publish, and the settlement system that finishes every trade one business day later.
If you are not yet sure what the thing being traded actually is, read what a stock is first. This guide assumes you know that a share is a fraction of a business, and picks up at the question of how that fraction changes hands.
The company gets paid once. After that, it is investors trading with each other
There are two markets stacked on top of each other, and beginners nearly always confuse them.
The primary market is where a company sells new shares and receives the money. That is an initial public offering, or a later offering by a company that is already listed. Cash goes into the business, new shares come out, and the company is genuinely being financed.
The secondary market is everything after that, and it is what people mean by “the stock market”. Here, existing shares move between investors. The company receives nothing.
Work it through with a real share count. Royal Bank of Canada reported 1,384,554 thousand common shares outstanding, about 1.38 billion, as at July 31, 2026 (Q3 2026 Report to Shareholders, p.43). If you buy 100 RY shares on the Toronto Stock Exchange tomorrow, you are buying 100 of those existing 1.38 billion from another investor who wanted out. No new share is created. Royal Bank’s bank account does not move. Its share count does not move. All that has happened is that a slice of the bank now sits in your name instead of somebody else’s.
This is worth holding onto, because it quietly answers a question new investors ask constantly: “am I helping the company by buying its stock?” Directly, no. What you affect is the price, and the price matters to the company in indirect ways: it sets the terms on which the company could issue new shares in future, it prices employee compensation, and it is the number a board gets judged on. But your purchase order does not put a dollar into the business.
It also explains why the price can move on a day when nothing at all happens inside the company. The price is not a measurement of the business. It is the level at which the last buyer and the last seller agreed, which is a fact about the two of them.
The order book: bid, ask, and the gap in between
Every listed stock has an order book, which is nothing more than a sorted list of what people have said they will do. Buy orders on one side, sell orders on the other, best prices at the top.
The following book is invented for teaching. No real company or ticker is involved, and the numbers are round on purpose.
Suppose the best bid is $20.00 for 300 shares and the best ask is $20.02 for 500 shares, with a further 1,000 shares offered at $20.10 behind that.
| Side | Price | Shares |
|---|---|---|
| Ask (someone will sell to you) | $20.10 | 1,000 |
| Ask (best) | $20.02 | 500 |
| Bid (best) | $20.00 | 300 |
Hypothetical order book, for illustration only.
The bid is the highest price anyone is currently willing to pay. The ask (also called the offer) is the lowest price anyone is currently willing to accept. The spread is the gap between them, two cents here. There is no single “price” sitting in the middle. There is a price you can buy at and a different, lower price you can sell at, at the same moment.
Now the two order types every investor needs, and the difference between them is the whole lesson.
A market order says “fill me now, at whatever the book offers.” Buy 100 shares at market and you take the ask: you pay $20.02 and you own them immediately. You have paid the spread for the privilege of certainty. Buy 800 shares at market in this book and the first 500 fill at $20.02, then that level is exhausted and the remaining 300 fill at $20.10. Your average price is worse than the quote you were looking at when you pressed the button, and nothing has gone wrong. That is simply what a market order does.
A limit order says “fill me at my price or not at all.” Enter a limit to buy at $20.00 and you join the bid, behind the 300 shares already queued there. You will pay $20.00 if a seller comes down to you. You may also sit there all day and never trade, and if the stock runs to $22 you will watch it go without you. A limit order controls your price and gives up certainty. A market order does the reverse. Neither is the correct choice in general, and choosing between them is one of the few genuinely consequential decisions in a beginner’s first year.
One more thing that trips people up. The “price” on your screen, the one quoted in the news, is usually the last trade: the price at which the most recent transaction actually happened. It is history. What you can transact at right now is the bid and the ask, and in a thinly traded stock those can sit a long way from the last print.
Who is on the other side, and what liquidity really means
An order book only fills if somebody is already standing there with an order in it. That standing willingness to trade is what liquidity means: how much you can buy or sell, how quickly, without pushing the price around.
In a heavily traded stock, the book is deep. There are many buyers just below the last trade and many sellers just above it, the spread is narrow, and a normal retail order is small against the volume already resting there. You get filled at close to the quote, and you barely notice the mechanics existed.
In a lightly traded stock, the book is thin. There may be very little sitting near the last price on either side, the spread can be wide, and an order of ordinary size can be large relative to what is on offer. The mechanics stop being invisible. This is a structural property of the market, not a judgement about the company, and it is the biggest practical difference between the two Canadian exchanges we get to below.
Market makers exist to soften this. A market maker is a firm that commits to quoting both a bid and an ask in an assigned stock, so that there is something in the book even when no natural buyer or seller happens to be around. It earns the spread as compensation for standing there and carrying the inventory risk. The Toronto Stock Exchange runs a formal market maker program. The useful takeaway for an investor is not the mechanics of that program: it is that the smooth two-sided quote you see on a large stock is partly a service somebody is paid to provide, and it is thinner or absent where the economics do not support it.
The trading day, session by session
Canadian trading is fully electronic. TMX Group operates the exchanges and publishes the session structure, and in its own words, “TMX facilitates fully electronic trading on Canada’s premier equities Exchanges, Toronto Stock Exchange (TSX), TSX Venture Exchange (TSXV) and TSX Alpha Exchange (TSXA).”
Here is what the day looks like on the TSX and TSXV. All times are Eastern.
| Time (ET) | What happens | What it means for you |
|---|---|---|
| 7:00 AM to 9:30 AM | Pre Open. Orders may be entered, but will not be executed. A calculated opening price (COP) is displayed and continuously updated. | You can queue an order early. It sits there. Nothing trades, so an order entered at 7:05 is not “in” ahead of the market in any meaningful sense, it is waiting for the auction with everyone else. |
| 9:30 AM | Market on Open (MOO). All matching orders are executed at a single opening trade price. Orders that do not execute carry into the continuous limit order book. | Every opening order gets the same price. The open is an auction, not a race, which is why the first print can be well away from the previous close. |
| 9:30 AM to 4:00 PM | Continuous Trading. All regular order types are accepted. | This is the order book described above, running live. Orders match as prices cross. |
| 3:50 PM to 4:00 PM | Market on Close (MOC). An Imbalance Period begins at 3:50 PM, followed by a Freeze Period that starts at a random point between 3:56 and 3:57 PM. Trades publish at 4:00 unless a Price Movement Extension is required. | The close is an auction too. The randomised freeze means nobody can time the exact instant the book locks. |
| 4:00 PM to 4:10 PM | Price Movement Extension (PME), designed to solicit further liquidity to offset a remaining imbalance. | On days when the closing auction is left one-sided, the official close can take a few extra minutes to resolve. |
Session details from the TSX trading hours page, captured September 1, 2026.
The concept worth extracting from that table is the auction. Most of the day is continuous trading, where orders match as they cross. But the open and the close are different: orders pile up and then clear together at one price. That is why the opening and closing prints carry so much volume, and why a market order entered at 9:29 behaves nothing like a market order entered at 11:30.
Two exchanges, and the distance between them
Canada’s exchanges are old. TMX notes that its exchanges “have provided companies with access to equity capital for over 160 years.” Today the listings are split across the Toronto Stock Exchange, for established companies, and the TSX Venture Exchange, for earlier-stage ones. Same country, same trading sessions, very different populations of company.
The gap is easier to see than to describe.
Note the scale on that chart. It is logarithmic, meaning each step is a multiplication rather than an addition, because a linear scale cannot show these companies on one page at all. Royal Bank’s market capitalisation is roughly 1,480 times Li-FT Power’s. Both are Canadian listed companies, both trade on a TMX exchange, and a stock screener will happily show them side by side in the same list.
| Toronto Stock Exchange (TSX) | TSX Venture Exchange (TSXV) | |
|---|---|---|
| Who lists there | Established companies. The examples below are a bank, a technology company, a pipeline and a retailer. | Earlier-stage companies. The examples below are all lithium exploration and development names. |
| Example companies (market cap, C$) | Royal Bank $391.9B, Shopify $252.5B, Enbridge $154.1B, Aritzia $14.6B | Sigma Lithium $1.9B, Li-FT Power $264.1M, Critical Elements Lithium $88.2M, Power Metals $86.4M |
| What to expect on liquidity | Expect deeper books and narrower spreads at this size, where a retail order is small against the volume already resting | Expect thinner books at this size: spreads can be wide, and an ordinary order can be large relative to what is on offer |
| What to expect on risk | Companies far enough along to have a reporting history you can read in their own filings | Companies that may be pre-revenue, and that commonly finance themselves by issuing new shares |
| Path between them | Where a TSXV company arrives if it succeeds | TMX runs a formal graduation process for companies moving up to the Toronto Stock Exchange |
Market capitalisations: Yahoo Finance market data, data as of September 1, 2026. Market caps move with the share price and will differ by the time you read this.
That last row matters. The TSXV is not a lesser market so much as an earlier one. A company that grows into a real business can graduate to the Toronto Stock Exchange through a formal TMX process. The exchange a company sits on tells you roughly what stage it is at, which is genuinely useful information and nothing more than that.
If you want to see the two ends of that spectrum with actual companies attached, our blue chip Canadian stocks page covers the established, dividend-paying end of the TSX, and our Canadian penny stocks page covers the speculative end, including what the risks actually look like in practice.
After you click buy: settlement, and who is watching
Your order fills in a fraction of a second. The trade is not finished at that moment. Settlement is the step where the shares and the cash actually change hands, and Canada runs on a T+1 cycle: one business day after the trade.
Canada moved to T+1 in 2024, and the coordination was run by the Canadian Capital Markets Association, whose T+1 Committees operated from 2021 to 2024 and whose board declared the T+1 implementation a success on October 31, 2024. The CCMA is the successor to Canada’s G-30 Working Group, which it describes as “mandated to make the global securities settlement cycle more efficient and secure by shortening securities settlement from T+5 to T+3 in 1995”. Read those two dates together and you can see the direction of travel over three decades: five days, then three, now one.
Why an investor should care about a piece of plumbing:
– A trade and a settled trade are two different events. Your order filling is the agreement. The shares and the cash move one business day later, and that later date is when the ownership change is finished. – Cash from a sale is not in hand on the day you sell. What your broker allows you to do with unsettled proceeds in the meantime is worth asking about before you need the answer, not after. – Anything with a hard cut-off runs on the settled date, so if a deadline matters to you, count backwards from it rather than assuming a fill on the day is enough.
Two bodies stand behind all of this. The Canadian Investment Regulatory Organization (CIRO) oversees investment dealers and marketplace trading in Canada, so it is the body concerned with your broker and with how trading is conducted. Securities regulation itself is provincial in Canada, and the provincial regulators coordinate through the Canadian Securities Administrators. The division of labour is worth remembering: exchanges set listing requirements, and regulators police conduct and disclosure. Neither one vets whether a listed company is a good investment, and neither is claiming to.
There is one more consequence of clicking sell, and it is the one people forget until spring. If you sell at a profit in a taxable, non-registered account, tax follows the gain. Our capital gains tax calculator shows how much on your own numbers. The way to avoid that question in the first place is to hold the shares somewhere sheltered, which is what registered accounts are for: see how a TFSA works for the most flexible of them. Where you hold a share changes what you keep from it, and that decision is better made before you buy than after.
The mistake that costs the most
The expensive beginner error is assuming that everything listed on “the stock market” is the same kind of thing, and then trading a TSX Venture company the way you would trade Royal Bank.
Three things go wrong, and they compound.
The order book is not the same shape. In a thinly traded stock, a market order can fill far away from the last price you saw, because it takes whatever thin liquidity is resting and keeps going up the book. The habit of typing in a market order because it always worked fine on a big name is exactly the habit that produces a fill you cannot explain. In thin names, the limit order is not a refinement. It is the default.
A listing is not an endorsement. An exchange sets listing requirements and enforces them. That is a floor, not a verdict, and nobody at TMX, CIRO or a provincial commission is telling you a company will succeed. The fact that something appears on the same screen, in the same format, with the same kind of chart as a bank carrying $391.9 billion of market capitalisation says nothing whatsoever about the two being comparable propositions.
Dilution is a live risk, not a footnote. Companies at the venture stage commonly finance themselves by issuing new shares, which is the primary market in action. Every new share issued makes each existing share a smaller slice of the same business. This is where the share-count lesson from our guide to what a stock is, linked above, stops being theory and starts being money: watch the share count, not only the share price, because a company can grow while your slice of it shrinks.
One last confusion is worth clearing up, because it produces a surprising amount of muddle. The exchange, the index, and the market are three different things. The TSX is an exchange, a venue where trading happens. The S&P/TSX Composite is an index, a calculated number that tracks a selected basket of listed companies. “The market” is the whole of it, across every venue. When someone says “the TSX was up today”, they almost always mean the index, and the index is not the same thing as the exchange or as every stock listed on it. An individual holding can move the opposite way to the index on the same day, and there is nothing strange about that at all.
Where to go next
You now know the shape of the machine: a second-hand market in existing shares, matched through an order book, opened and closed by auction, kept quotable in part by firms paid to stand in the middle, split across a senior and a venture exchange, and finished off one business day later by a settlement system almost nobody ever sees.
None of this machinery is usable until you have an account to trade from. Our guide to opening a brokerage account in Canada covers the account types, what the application asks and why, and how to fund it.
The links through this guide are the path onward. The guide to what a stock is covers the thing being traded here, the blue chip and penny stock pages put real companies on the two ends of this market, and the TFSA guide and the capital gains calculator settle the question of where your shares should sit and what it costs to get that wrong.
One habit to take with you. When something about a trade surprises you, the answer is usually structural rather than mysterious: the spread, the depth of the book, the auction, or the settlement date. The rules of this market are written down and published by the exchanges and the regulators themselves, and reading the source beats reading a summary of it every time.