Fractional Trading and Minimum Trading Units

Originally, '1 share' is the minimum trading unit for a stock. That is, you couldn't buy with less money than the price of 1 share. So expensive stocks costing hundreds or thousands of dollars per share were hard for small investors to access.

Fractional trading lowers this wall. It's a method that slices 1 share finely so you can buy even less than 1 share, like 0.1 share or 0.05 share. For example, even a stock at about $740 per share can be bought in an amount of about $74 (0.1 share). It became possible to diversify into expensive stocks with a small amount.

The principle is this: typically the brokerage gathers many investors' fractional orders, buys actual shares in whole-number units, and then slices the ownership finely to allocate it to each investor.

Fractional trading is especially useful for small-amount, recurring investing. You can buy an expensive stock little by little with a set amount each month (for example, about $74), making it easier to steadily accumulate on an amount basis.

However, there are a few things to note. Fractional orders are sometimes not executed in real time but processed in batches at a specific point, so it can be hard to buy at exactly the price of the moment you want. Also, some shareholder rights, such as exercising voting rights, may be restricted, and processing the fractional portion can be cumbersome when transferring to another brokerage.

And remember that when buying overseas stocks fractionally, currency exchange (the exchange rate) and fees also apply. Rather than 'it's a small amount so there's no cost,' the fee and exchange rate effects work just the same even for small amounts.