Risk Management · Intermediate
How Much Margin Do You Need to Sell One Lot of Nifty Options?
Selling a Nifty option is nothing like buying one. A buyer pays a premium and is done; a seller must post margin — often ₹1.25 to ₹1.5 lakh per lot — and carries far larger risk. Here is what that margin is made of, how much one lot really needs, and the simple trick that cuts it by up to 90%.
Why sellers pay margin and buyers do not
When you buy an option, your maximum loss is the premium you pay, so the exchange needs no further security — you cannot lose more than you already handed over. When you sell (write) an option, you collect a small premium but take on a potentially large loss if the market moves against you. To cover that, the exchange blocks margin in your account for as long as the position is open.
What the margin is made of: SPAN + exposure
Your total selling margin has two parts:
- SPAN margin — the exchange's estimate of the worst-case one-day loss on your position, calculated by a risk model that scans a range of price and volatility moves.
- Exposure margin — an extra buffer on top of SPAN.
Together they are the money locked up to let you carry a short option overnight. Since February 2025, SEBI requires brokers to collect the full upfront margin for overnight F&O, so there is no carrying a naked short "on low margin".
How much for one lot of Nifty and Bank Nifty
As a normal-volatility rule of thumb in 2026, with Nifty near 24,850 (lot size 65):
- Nifty option selling: roughly ₹1.25 to ₹1.5 lakh per lot.
- Bank Nifty option selling: higher, roughly ₹1.5 to ₹1.9 lakh per lot, because it moves more.
- Buying either: just the premium — no SPAN or exposure margin at all.
These are estimates. The exact figure is set by the exchange, changes daily with volatility, and jumps around results and big events.
Pick Nifty or Bank Nifty, enter your spot and lots, and the calculator estimates SPAN + exposure margin — and shows how much a hedge saves.
Open the margin calculator →The trick that cuts margin by up to 90%: hedge it
Sell an option and buy a further one against it — a spread — and your maximum loss becomes capped. Because the exchange only needs to cover that capped loss, it blocks far less margin.
Example: a naked short Nifty option might block around ₹1.45 lakh. Turn it into a 200-point-wide credit spread and the margin can fall to roughly ₹9,000 to ₹13,000 — a reduction of well over 90%. You give up some premium for the hedge, but your capital goes much further and your worst case is defined.
You can see this side by side in the margin calculator's hedged mode, and map the resulting payoff in the payoff calculator.
Margin is not a one-time number
Two things traders forget:
- It moves. SPAN is recalculated through the day. If volatility spikes or Nifty trends hard, your blocked margin can rise while the position is open — keep a buffer so you are not forced to exit.
- Costs are separate. Margin is capital locked up, not a cost. Brokerage, STT and taxes are separate — estimate them in the brokerage calculator.
Before committing capital, it is worth reading how to size each position and how much capital you actually need.
Nifty option selling margin FAQ
How much margin to sell one lot of Nifty options?
Roughly ₹1.25 to ₹1.5 lakh per lot at normal volatility in 2026, made up of SPAN plus exposure margin. Bank Nifty needs more. The exact figure changes daily — confirm with your broker's margin calculator.
Do option buyers need margin?
No. Buying an option costs only the premium, which is also your maximum loss, so there is no SPAN or exposure margin.
How do I reduce the margin on a short option?
Hedge it into a spread by buying a further option. The capped loss means the exchange blocks far less — often 80 to 90% less than a naked short.
Can my margin increase after I enter?
Yes. SPAN margin is recalculated intraday and rises with volatility and around events. Keep spare capital so a margin increase does not force you out.
Margin figures are educational estimates using normal-volatility rates; real SPAN + exposure margins are set by the exchange and change daily. Nifty lot size 65 and Bank Nifty 30 are the NSE values effective from the January 2026 revision. NiftyWise.org is an educational platform and is not registered with SEBI as an Investment Adviser, Research Analyst, or Stockbroker. Options selling carries a high risk of loss — SEBI's July 2025 study found 91% of retail F&O traders lost money in FY2024-25. Consult a SEBI-registered Investment Adviser before trading. Visit sebi.gov.in to verify credentials.
