NSE Implements Revised Lot Sizes for Index F&O Contracts from January 2026 Series
NSE will implement revised lot sizes for major index derivatives from January 2026 contracts, with Nifty 50 reduced from 75 to 65 units and Bank Nifty from 35 to 30 units. The changes affect weekly contracts from January 6, 2026 expiry and monthly contracts from January 27, 2026 expiry, while December 2025 contracts continue under current lot sizes.
*this image is generated using AI for illustrative purposes only.
The National Stock Exchange (NSE) will implement revised lot sizes for major index derivatives starting from the January 2026 contract series, following an earlier circular announcement. The changes will take effect from the expiry cycle following December 2025, impacting all contracts in the January 2026 series and beyond.
Revised Lot Size Framework
The NSE has announced specific reductions in lot sizes for four major index derivatives to better align with current market conditions.
| Index: | Current Lot Size | Revised Lot Size | Reduction |
|---|---|---|---|
| Nifty 50: | 75 units | 65 units | 10 units |
| Bank Nifty: | 35 units | 30 units | 5 units |
| Nifty Financial Services: | 65 units | 60 units | 5 units |
| Nifty Midcap Select: | 140 units | 120 units | 20 units |
The lot sizes for other indices, including Nifty Next 50, will remain unchanged under the current framework.
Implementation Timeline
The transition will follow a structured timeline to ensure smooth market operations. Weekly and monthly contracts expiring in December 2025 will continue trading under current lot sizes, with the revised framework applying exclusively to January 2026 series onwards.
| Contract Type: | Last Contract (Current Lot Size) | First Contract (Revised Lot Size) |
|---|---|---|
| Weekly Derivatives: | December 23, 2025 expiry | January 6, 2026 expiry |
| Monthly Contracts: | December 30, 2025 expiry | January 27, 2026 expiry |
| Quarterly/Half-yearly: | End of December 30, 2025 | From January 2026 series |
Contract Transition Details
The March 2026 contract, originally launched as a quarterly expiry, will be treated as a far-month contract under the new lot size regime starting from the end of the December 2025 monthly cycle. This ensures consistency across all contract types during the transition period.
Quarterly and half-yearly contracts will adopt the revised lot sizes from end of day December 30, 2025, maintaining uniformity with the monthly contract transition schedule.
Market Impact and Rationale
These periodic revisions by the NSE aim to align notional contract values with prevailing index levels, maintaining efficient market functioning and ensuring manageable position sizing for both retail and institutional traders. The adjustments reflect the exchange's commitment to optimizing derivative market structure as underlying indices evolve.
Market participants are advised to review their open positions and risk exposure as the transition approaches. Brokers are expected to update trading platforms and margin calculators to reflect the revised lot sizes in time for the January 2026 series launch.
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