What Is the Minimum Number of Shares for a Buy Order?

Investors place a “buy order” to acquire shares of a company. This instruction is submitted to a brokerage. A buy order allows individuals to become owners of publicly traded companies. It contrasts with a “sell order,” which is an instruction to divest shares.

The Standard Minimum for Shares

Traditionally, the smallest unit of ownership an investor could acquire in a public company was one whole share. For most publicly traded stocks, a buy order can still be placed for as little as a single share. This one-share minimum has long been the fundamental unit for individual stock purchases.

Historically, the stock market recognized “round lots” (100 shares or multiples) and “odd lots” (fewer than 100 shares). While these terms still exist, they generally do not impose a minimum purchase quantity for individual investors today. Advancements in trading technology mean these historical concepts rarely dictate the minimum number of shares an individual investor can buy.

Fractional Shares and Accessibility

The modern investment landscape includes “fractional shares,” which are portions of a single share of a company’s stock. This innovation allows investors to buy a specific dollar amount of a stock, rather than a fixed number of shares. For example, an investor can choose to invest $50 in a stock, even if a single share costs $200, acquiring a quarter of a share.

Fractional shares enhance accessibility to investing, particularly for high-priced stocks that might otherwise be out of reach for individuals with smaller budgets. This enables investors to diversify their portfolios more effectively by spreading smaller amounts of capital across a wider range of companies. Fractional shares also facilitate strategies like dollar-cost averaging, where a fixed amount of money is invested regularly, regardless of the share price, to smooth out market volatility. While fractional shares offer many benefits, they can only be purchased and sold through participating brokerages, and sometimes come with limitations such as restricted voting rights or transferability issues.

Brokerage Specifics and Practical Considerations

While the technical minimum for purchasing shares is often one, or even a fraction of a share, practical considerations related to brokerage accounts can influence an investor’s ability to place small orders. Some brokerage firms may require a minimum initial deposit to open an account. This requirement, which can range from no minimum to as high as $2,500, indirectly sets a higher entry barrier than the cost of a single share.

Even if a brokerage has no minimum deposit, the inherent price of a single share remains a practical consideration for investors with limited funds. For instance, buying one share of a stock priced at several hundred dollars may still be a significant investment for some. These factors are not “minimum share” requirements imposed by the market itself, but financial considerations and brokerage policies that affect the feasibility of small investments. Many brokerages now offer commission-free trading, making it more practical to buy a small number of shares without disproportionate transaction costs.