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Many investors when first encountering stocks are often confused by one question — why does trading in US stocks seem so cheap, but in Taiwan stocks it costs so much? The simple reason behind this is: the trading unit rules are completely different in each market.

What is stock price? In what unit is it quoted?

In the stock market, the stock price refers to the trading price of each share, representing how much investors need to pay to buy one share, or at what price they sell.

Stock prices fluctuate in real-time based on supply and demand from buyers and sellers. Different countries’ stock markets use different currencies for pricing. US stocks are priced in USD, Taiwan stocks in NTD, and Hong Kong stocks in HKD. For example, TSMC’s stock price might be 1080 NTD per share, while Tesla in the US might be 254 USD per share.

What is a share? How much does one share cost?

One share is the smallest trading unit in the stock market. To raise funds, listed companies divide ownership into several parts, each called a share.

The specific value of one share depends on the current market price. For example, in August 2023, Tesla (TSLA) in the US was priced at 254.11 USD per share, meaning buying one share costs 254.11 USD. A few months earlier, in January 2023, Tesla was only 101.81 USD per share, so the price doubled.

The same logic applies to Taiwan stocks. For example, a certain time TSMC (1101.TW) stock price was 32.10 NTD per share, so investors need to pay 32.10 NTD to buy one share.

Note that the face value of stocks (for example, the old Taiwan stock regulation’s 10 NTD face value) has nothing to do with the current stock price. The face value is just a historical record; the real price is determined by the company’s earning capacity and investors’ perceptions.

How many shares are in one sheet of Taiwan stock? How do trading units differ across markets?

This is the key difference — the trading unit rules vary completely across countries’ stock markets:

• US stocks: The trading unit is 1 share. You can buy 1, 2, or 100 shares — very flexible.
• Taiwan stocks: The trading unit is 1 sheet. One sheet equals 1000 shares, meaning you cannot buy just a few shares; you must buy at least one sheet (1000 shares).
• Hong Kong stocks: The trading unit is called 1 lot. But HK stocks are a bit special — one lot can be 100, 500, 1000, or 2000 shares, depending on the stock’s price.

Cost comparison

As a result, the investment costs vary greatly:

Tesla in the US: current quote is 420 USD per share, so trading one share costs only 420 USD.

TSMC in Taiwan: current quote is 1080 NTD per share, so trading one sheet costs 1080 × 1000 = 1,080,000 NTD.

Tencent in Hong Kong: current quote is 418 HKD per share, and one lot is 100 shares, so trading one lot costs 418 × 100 = 41,800 HKD.

A simple comparison shows that US stocks are the most flexible and cheapest, Taiwan stocks require the most initial capital, and Hong Kong stocks are in between.

Why is it designed this way?

This is all a product of history and market rules. Taiwan continued using the fixed face value system from early years, which locked the minimum purchase unit at 1000 shares. When US stocks rose to prominence, technological advances made small transactions possible, so a more flexible 1-share rule was established. Hong Kong stocks found a balance between the two.

Ultimately, choosing which market to invest in depends on your capital size and risk tolerance.