Foundation Lesson 3 of 7
Foundation · Lesson 3 of 7

How Stock Prices Move

Why share prices move every day — the gap between reality and expectation, how UK and US markets digest earnings, and why "good news" can still send a stock down.
· Updated 1 June 2026· 8 min read beginner

How Stock Prices Move: The Secret Language of Markets

Welcome, friend. It’s a funny old world, isn’t it? We often look at the stock market like it’s a mystical beast that does whatever it pleases. But if you peel back the layers, you’ll find that prices are actually quite logical. They are just a conversation happening between buyers and sellers.

This lesson will strip away the noise and show you exactly what drives stock prices. The secret? It’s not about how "good" a company is; it’s about what people expect to happen.


What is a Stock Price, Really?

At its simplest, a stock price is the most recent price where a buyer and seller agreed to trade.

Think of it like a photograph. It captures a single moment in time. It is not a permanent tattoo on the company’s soul, nor is it a guaranteed promise of the future. A price simply tells you what the market is willing to pay right now for a slice of that company.

The Mechanics of a Trade

To understand price, you have to look at the "Bid-Ask" spread. It’s like a used car dealership.

  • The Bid (The Offer): This is the highest price a buyer is willing to shout out right now. Think of this as the "give me a price to take this off your hands" moment.
  • The Ask (The Demand): This is the lowest price a seller is willing to whisper. Think of this as the "I won’t take less than this" moment.
  • The Last Price: This is where the rubber meets the road-where a transaction actually happens.

When expectations change, the shouts and whispers change, and the price moves to match the new reality.


The Core Driver: Expectations, Not Events

The most important lesson you will learn in finance is this: Markets are forward-looking.

Stock prices move when reality differs from what was already expected. They don't move because something happened; they move because something surprised us.

How the Surprise Works

Imagine your favorite restaurant announces a new menu. If the menu is exactly what you expected, the stock price of the restaurant (or its parent company) might not change much. But if the menu is way better than you hoped, or if it’s a disaster, the price will jump or drop.

Let’s look at how this plays out with numbers, a scenario known as "Beating or Missing Estimates":

  1. Earnings Beat Expectations: The company makes more money than Wall Street predicted.
    • Result: The price usually rises.
  2. Earnings Beat Expectations But Less Than Hoped: The company makes money, but not as much as stockholders really wanted.
    • Result: The price usually falls.
  3. Earnings Miss Expectations But Outlook Improves: The company lost money today, but they promise to be profitable next year.
    • Result: The price might rise.

See? It’s not about the raw numbers; it’s about the gap between the numbers and the prediction.


The Expectation Gap Framework

To master this, you need to understand the "Expectation Gap." It is the space between what the market believed would happen and what actually happened.

  • Consensus Expectation: What the "smart money" and the average investor collectively believe will happen.
  • New Information: The actual results, news articles, or government data.
  • The Gap: The difference between the two.
The GapPrice ReactionWhy?
Better than expectedPrice RisesInvestors get excited; they are willing to pay more.
Worse than expectedPrice FallsInvestors are disappointed; they won't pay as much.
In line with expectationsLittle movementThe market isn't surprised. It’s just business as usual.

This explains why a fantastic company can sometimes see its stock price drop. It’s not because the company is failing; it’s because the stock price was already priced for perfection. When reality matches the perfection, there is no excitement, just a flat line.


The Invisible Hand: Supply, Demand, and Liquidity

Information alone doesn't move prices. There is a second force at play: Liquidity. This is simply how easily you can turn an asset into cash without dropping the price.

Imagine you want to sell a rare comic book. You might have to wait a long time to find a buyer, and you might have to accept a lower price to get someone to take it off your hands quickly. This is low liquidity.

Now imagine you want to sell a crate of apples. You can find a buyer in seconds for the market price. This is high liquidity.

  • Low Liquidity: Prices can swing wildly on very small trades.
  • High Liquidity: Prices are more stable; it takes a lot of money to shift them.

Who is Moving the Market?

It is easy to feel like the market is controlled by a cabal of wizards. In reality, it is a mix of different players, and they all have different motives.

  • Retail Investors (You and Me): We trade based on news, tips, and emotions. We have high participation but smaller amounts of money. We tend to move the needle in smaller, less popular stocks.
  • Institutional Investors (Banks, Pension Funds, Hedge Funds): These are the heavyweights. They manage trillions of dollars. They trade based on complex models, mandates, and risk management. When they buy or sell, prices move significantly.
  • Market Makers: These are the referees of the game. They are constantly buying and selling to ensure there is always a buyer or seller available. They adjust their prices based on how risky or volatile the stock is.
  • Passive Investors (ETFs): These are index funds that just buy everything in an index automatically. They don't care if a company is "good" or "bad"; they just follow the rules.

When you hear "the market thinks," it usually refers to the collective positioning of the Institutional Investors.


Time Horizons: Don't Use a Hammer to Swat a Fly

Different investors look at the clock differently. This causes a lot of confusion.

  • Short-Term (Days/Weeks): Driven by News and Flows. Traders are reacting to headlines, rumors, and technical patterns.
  • Medium-Term (Months): Driven by Revisions and Narratives. Investors are asking, "Is the business story getting better or worse?"
  • Long-Term (Years): Driven by Fundamentals. Are the company's profits growing? Is the debt manageable?

The biggest mistake beginners make is looking at a short-term chart and trying to apply long-term logic. A stock might drop 50% in a day due to a bad headline, even though the company is fundamentally strong. Conversely, a great company can stagnate for years because the market thinks it can't grow any faster.


Volatility Is Not Direction

We often hear people say, "The market is so volatile!" But volatility doesn't tell us if the market is going up or down. It only tells us how uncertain the market is.

  • High Volatility: Expectations are unstable. Nobody agrees on what the stock is worth. The price is bouncing around like a pinball.
  • Low Volatility: Expectations are aligned. Everyone agrees the stock is worth about $50. The price stays close to $50.

Why Headlines Often Feel Wrong

This is perhaps the most frustrating part for beginners. You see a scary headline, expecting the stock to crash, but it actually goes up. Why?

Because Markets react to what is already priced in.

By the time a news story hits your phone or TV screen:

  1. The big institutions have already analyzed the data.
  2. They may have already bought or sold the stock based on that analysis.
  3. The price movement has likely already happened.

Markets often look irrational because they react to information before the general public even realizes the information exists. The public sees the result; the market sees the cause.


Common Misconceptions

Let’s clear up a few myths that float around the tavern:

  • "Good companies always go up." False. A "good" company can be overvalued. If you pay $100 for a $10 bill, you have a "good" bill, but you have a bad investment.
  • "Bad news always causes sell-offs." False. Sometimes bad news removes uncertainty. If a company is in trouble, a "bad" result might be better than the terrifying unknown.
  • "Stock prices follow fundamentals." Incorrect. Stock prices follow changes in expected fundamentals. The price doesn't care about the past; it only cares about the future.

Summary

To wrap this up, here are the key takeaways to remember:

  1. Price is a Snapshot: It is the price of the last trade, not a judgment on the company's soul.
  2. Expectations Rule: Prices move based on the gap between what was expected and what happened.
  3. Liquidity Matters: It takes more money to move a big company's stock than it does a small one.
  4. News is Old News: By the time you see it, the price has likely already reacted.
  5. Short vs. Long: Don't use a long-term strategy to fix a short-term problem.

Once you start seeing price movement as a signal of shifting expectations rather than a moral judgment, the market becomes a lot less confusing. Keep your wits about you, and remember: in the market, hope is not a strategy.

Frequently asked

Common questions about How Stock Prices Move

Why did the share price fall after good news?
Because the share price had already priced in *better* news than what arrived. Markets are forward-looking — they trade on the gap between the consensus expectation and what actually happens. A profit that beats forecasts but misses the whisper number is treated as a disappointment.
What does "priced in" actually mean?
Priced in
How quickly does the UK market react to earnings releases?
For FTSE 100 names, almost instantly. Most large UK earnings are released at 7:00am before the LSE opens at 8:00am, and pre-market trading on dark pools and electronic networks usually has the share price re-rated by the open. Retail investors typically see the *outcome*, not the move.
What's the difference between volatility and direction?
Volatility measures how much a price bounces around — it says nothing about which way the price is going. A stock can have very high volatility and end the year flat. Low volatility means the market broadly agrees on the price; high volatility means it doesn't.
Why does a FTSE 100 share price move when nothing about the company has changed?
Because something about the *environment* changed. Interest rate decisions, currency moves, sector-wide news, index rebalances and even forced selling from passive funds can all move a share without the underlying business doing anything different.
Should I trade around earnings announcements?
For most UK investors, no. Earnings moves are dominated by expectation gaps you can't easily measure, by institutional positioning you can't see, and by overnight gaps that bypass any stop-loss you might set. Long-term holders typically benefit from ignoring earnings-day volatility entirely.
Do retail investors actually move share prices?
Rarely on FTSE 100 stocks — the volume from institutions dwarfs retail flow. But on smaller AIM-listed companies, retail buying can absolutely move prices, especially when a name goes viral on social media or financial press.