What is a Lot Size?

A lot size is the minimum number of shares you can buy or sell in one order. Think of it as a fixed bundle set by the exchange. So, if the lot size is 100, you can trade only in multiples of 100—like 100, 200, 300 shares. In corporate actions (like buybacks, rights issues, or bonus adjustments), the lot size sometimes changes based on the company’s share structure.