Browse Market Structure

Odd Lot

An Odd Lot refers to stocks or bonds traded in blocks of fewer than 100 shares. It is different from a round lot, which usually consists of 100 shares. This term is significant in trading as it can affect liquidity and transaction costs.

An Odd Lot, in the context of securities trading, refers to a quantity of stocks or bonds that is less than the standard block size, typically fewer than 100 shares. This is contrasted with a Round Lot, which consists of exactly 100 shares or multiples thereof. Odd lots can affect the market’s perception of trade size and transaction liquidity.

Mixed Lot

A Mixed Lot includes a round lot of 100 shares plus an odd number of additional shares beyond the round lot, such as 135 shares.

Mini Lot

A Mini Lot is smaller than the standard odd lot and typically consists of quantities like 10 shares.

Micro Lot

A Micro Lot is an even smaller segment, often used in forex trading, and consists of 1,000 units of currency.

Special Considerations for Odd Lots

Odd lots were historically more expensive to trade due to the lower liquidity and higher relative transaction costs. However, advances in electronic trading have largely mitigated these additional costs.

Applicability in Modern Markets

Modern trading platforms and practices have largely equalized the transactional landscape for odd lots, especially for retail investors. Many online brokers offer fractional shares, enabling investors to buy odd lots conveniently and inexpensively.

Odd Lot vs Round Lot

Odd Lot vs Block Trade

  • Odd Lot: Small quantities of fewer than 100 shares.
  • Block Trade: Large quantity trades, typically more than 10,000 shares.
  • Round Lot: A standard unit of trading, usually consisting of 100 shares.
  • Block Order: Large size orders generally exceeding 10,000 shares, used by institutions.
  • Fractional Share: Units of stock less than one full share, often involved in dividend reinvestment plans (DRIPs).

FAQs

Are transaction costs for odd lot trades higher?

Traditionally, yes, but advanced electronic trading systems have reduced these costs significantly.

How do odd lots impact liquidity?

Odd lots are less liquid than round lots, but the effect is minor in most modern trading environments.

Can institutional investors trade odd lots?

Yes, but they typically deal in round lots or block trades to maintain efficiency.
Revised on Monday, May 18, 2026