Introductory Context
"NSE futures have specific lot sizes, three active contract months at all times, daily MTM settlement, and a rollover mechanism at each monthly expiry. Understanding lot sizes, margin requirements, the roll cost, and how to read futures data makes you a more complete options market participant. "
NSE Futures Contract Structure
• the reference asset — Nifty 50, Bank Nifty, a specific stock. Underlying:
• minimum trading unit. Nifty 50: 75 units per lot (post-November 2024). Bank Nifty: 30 units. Stock futures: varies by stock. Lot size:
• three simultaneously active — near month (current), middle month (next), far month (month after). All trade at the same time. Contract months:
• last Thursday of the contract month for equity index and stock futures. If Thursday is a holiday, expiry shifts to the previous trading day. Expiry date:
• daily MTM in cash. Final settlement at expiry in cash for index futures, physical for most stock futures. Settlement:
Three Simultaneous Contract Months
On any trading day, three Nifty futures contracts are active: near-month, mid-month, and far-month. Near-month has the highest volume and tightest spreads. Options traders who look at Nifty futures typically focus on the near-month contract for current market signals.
Margin for NSE Futures
SPAN Margin
SPAN (Standard Portfolio Analysis of Risk) margin is calculated based on the worst-case loss a position could suffer under a defined set of market scenarios. For Nifty futures, SPAN margin is approximately 8–10% of contract value. With Nifty at 24,000 and lot size 75: contract value = ₹18,00,000. SPAN margin: approximately ₹1,44,000–₹1,80,000.
Exposure Margin
An additional 3–5% buffer on top of SPAN. Total initial margin for Nifty futures is typically ₹1,60,000–₹2,00,000 per lot under normal conditions. During high-volatility periods, NSE increases requirements — sometimes doubling them.
Margin Call Reality
A margin call means: deposit the shortfall before the next trading session opens, or the broker closes your position at the next available price. There is no grace period. If global markets move overnight and your Nifty futures position is significantly offside, the margin call may arrive at 7 AM. Always maintain 20–30% buffer above minimum margin when holding futures positions overnight.
The Futures Roll — Reading Market Sentiment
As the near-month contract approaches expiry, traders maintaining positions must roll — close the expiring contract and open the next month's contract. The pattern of this rollover tells you about institutional positioning.
The key data point is roll cost — the price difference between the expiring near-month and the mid-month contract. High roll cost signals strong demand for the next month, indicating bulls aggressively rolling long positions rather than exiting. Low or negative roll cost suggests bearish positioning.
Rollover Data for Options Traders
NSE publishes daily rollover data in the last week of each month — showing what percentage of near-month OI has rolled to the next month. High rollover at high cost: bullish sentiment carrying forward. Low rollover or low cost: bearish or uncertain. Check this each Thursday of expiry week for context on the following month's directional bias.