What Is Lot Size in F&O?
You can’t trade a single share in derivatives — you trade in fixed lots. Here’s what lot size means and why it matters.
On this page
In the futures and options (F&O) segment, you can’t trade just one share — contracts come in a fixed lot size set by the exchange. One contract = one lot = a defined number of units of the underlying.
How lot size works
Each F&O stock or index has a specified lot size (for example, an index option lot might be 25, 50 or 75 units, revised periodically by the exchange). You trade in multiples of a lot — 1 lot, 2 lots, and so on — never a fraction.
Why it matters
- It sets your real exposure. The notional value of a position = lot size × price. A "small" premium can control a large notional amount, which is how leverage builds up.
- Minimum ticket size — because you buy a whole lot, the minimum capital and margin for one F&O trade can be substantial.
- Position sizing — since you can only add in whole lots, lot size limits how finely you can size risk — important for small accounts.
The freeze quantity
Exchanges also set a freeze quantity — the maximum number of lots you can put in a single order. Larger orders must be split, a safeguard against fat-finger errors.
The takeaway
Always compute the full contract value (lot size × price), not just the premium, before trading — it’s the true exposure and risk. Lot sizes change, so check the current one. Derivatives are high-risk. Education only, not advice.
