Round Lot

The normal unit of trading for a security, which is generally 100 shares of stock.

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Anything less than 100 shares is considered an odd lot.

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Generally accepted unit of trading on a securities exchange. On the New York Stock Exchange, for example, a round lot is 100 shares for stock and $1,000 or $5,000 par value for bonds. In inactive stocks, the round lot is 10 shares. Increasingly, there seems to be recognition of a 500-share round lot for trading by institutions. Large denomination Certificates of Deposit trade on the Over the Counter market in units of $1 million. Investors who trade in round lots do not have to pay the Differential charged on Odd Lot trades.

Unit of trading on a securities exchange. For example, a round-lot on the New York Stock Exchange (NYSE) is 100 shares of stock or one $1000-face-value bond (although brokers may have their own higher round-lot requirements in the case of bonds). Inactive stocks have a 10-share round-lot. See also Odd-Lot.