Why is the stock market falling?

Markets fall for four reasons and only one of them changes what a company is worth. Here is how to tell which you're looking at, what to check in your own holdings, and why a falling price is information about sentiment rather than about business value.

By Nathan Wickham-Hurd · Founder, Oak Growth · First-class Economics & Finance, MBA · Last reviewed August 2026

The short answer

Markets fall for one of four reasons, and it is usually worth knowing which one you are looking at before doing anything.

1. The discount rate moved

Interest rate expectations rose, so future company cash flows are worth less today. Nothing changed at the businesses themselves — see what happens to stocks when interest rates rise.

2. Expected earnings fell

A recession signal, a demand shock, a sector-wide disappointment. This one is real: the cash the businesses will produce is genuinely lower than the market previously assumed.

3. Positioning unwound

Leveraged investors reduce exposure, forced sellers sell what they can rather than what they want to, and the selling feeds on itself. This has no connection to company value at all.

4. Fear

A shock — conflict, a bank failure, a policy surprise — and people sell first and analyse later. Historically the largest falls have a large component of this.

Only the second one changes what a business is worth. The other three change what people will pay for it, which is a different thing entirely.

Price and value are not the same number

This is the single most useful idea in investing and the hardest to feel during a fall. A company's intrinsic value is the cash it can generate for its owners over its life, discounted to today. That figure does not move 4% because of a headline. The share price does.

Share price = what people will pay today Intrinsic value = what the business is worth A fall widens the gap. It does not shrink the value.

When a business you have valued at 800p trades at 900p, you wait. When a market-wide fall takes it to 650p and nothing has changed operationally, the thing you wanted got cheaper. That is the entire mechanism by which value investing works, and it only ever presents itself during falls.

The question to actually ask

Not “why is the market down” but “has anything changed about what my companies will earn?” Work through it business by business:

Has demand for what they sell changed?

A recession genuinely hurts a housebuilder. It barely touches a business selling medicines or electricity.

Can they survive it?

Check debt maturing in the next two years and whether operating profit covers the interest bill several times over. Companies rarely die from falling profits; they die from refinancing at the wrong moment. See debt to equity.

Do they need the market's money?

A business that funds itself from its own free cash flow is indifferent to a closed equity market. One that was planning a rights issue is not.

Does the fall change the moat?

Almost never. Downturns often widen moats, because weaker competitors cut investment or disappear entirely.

What the historical record says

Falls of 10% happen roughly every year or two. Falls of 20% or more have happened many times in every investor's lifetime. In each case the recovery was invisible at the time and obvious afterwards. The investors who did badly were overwhelmingly the ones who sold during the fall — not the ones who bought at the top.

This is not a claim that any particular fall will recover, or that shares always go up. It is the observation that a decline in price, on its own, tells you nothing about a business. You still have to do the work on each company, and some genuinely deserve to be marked down.

The one thing that actually protects you

Deciding what a company is worth before the fall. If you already know your number, a 20% decline is arithmetic: the margin of safety just widened from 5% to 24%, and you act or you don't. If you don't have a number, a fall is pure emotion, and emotion has no good decision in it.

Know your number before the next fall

Oak Growth estimates intrinsic value and margin of safety for roughly 1,000 companies across nine markets, so when prices drop you already know which businesses just got cheaper.

Explore Oak Growth

Common questions

Why is the stock market falling?

Usually one of four things: interest rate expectations rose, expected company earnings fell, leveraged investors were forced to reduce positions, or a shock triggered broad selling. Only the second genuinely changes what businesses are worth — the other three change what people will pay for them.

Should I sell when the stock market is falling?

Selling during a fall converts a paper decline into a realised one, and historically the investors who did worst were those who sold during declines rather than those who bought before them. The useful question is whether anything changed about what your companies will earn, not what the price did this week.

How often does the stock market fall?

Declines of around 10% have historically occurred roughly every year or two, and falls of 20% or more have happened many times within a typical investing lifetime. Frequency is not a forecast — it simply means falls are a normal feature rather than an emergency.

Is a market fall a good time to buy shares?

It can be, but only for businesses you have already valued. A lower price widens the margin of safety on a company whose earnings power is unchanged. It does nothing for a company whose earnings are genuinely deteriorating, and telling the two apart is the actual work.

Also see: Margin of safety → · Stocks and rising interest rates → · What is a value trap? →