- The official change-over: weekly and monthly contracts
- What happens to existing long-dated options
- Liquidity, spreads, and basis around roll windows
- Desk checklist and FAQs
The short
- What changed: All index and single-stock derivatives on NSE move from Thursday expiry to Tuesday.
- Effective window: Existing contracts expiring on/before Aug 31, 2025 keep their original schedule; newly generated contracts with expiries on/after Sep 1, 2025 follow Tuesday.
- Realignment: Long-dated NIFTY & BANKNIFTY options (Sep ’25 onwards) are re-aligned to Tuesday via contract master updates.
- BSE alignment: BSE has indicated it will host Thursday expiries to avoid a same-day clash.
Contract-by-contract: old vs new
| Instrument | Old expiry | New expiry | Notes |
|---|---|---|---|
| NIFTY (monthly/quarterly/half-yearly) | Last Thursday | Last Tuesday | Long-dated options from Sep ’25 re-aligned to Tuesday. |
| NIFTY (weekly) | Thursday | Tuesday | New weekly chains generated as Tuesday expiries per cut-over. |
| BANKNIFTY (monthly/quarterly) | Last Thursday | Last Tuesday | Contract master updated at scheduled EOD. |
| FINNIFTY / MIDCPNIFTY / NIFTYNXT50 (monthly) | Last Thursday | Last Tuesday | No other spec changes. |
| All single-stock derivatives (monthly) | Last Thursday | Last Tuesday | Sep ’25 expiries onward generated as Tuesday. |
This page summarises the exchange circulars for quick trading reference. Always confirm dates in the live contract master files.
Trading & risk implications
- Spread & depth: Expect transient widening and “learning” phase for market makers; use limit orders on first few Tuesday expiries.
- Basis & calendars: Calendar spreads may reprice; watch ETF/AP activity and basis kinks around the new roll cadence.
- Cross-venue hedges: If you run NSE–BSE hedges, note the non-overlap of expiry days (Tue vs Thu) and adjust carry/roll models.
- Vol surface: Day-of-week seasonality shifts; re-estimate skew dynamics around Tuesday fixes.
Desk checklist
- Refresh contract.gz / MII-Contract.gz files and rebuild symbol maps.
- Backtest rolls with Tuesday nodes; revisit auto-hedge and stop logic around expiry.
- Coordinate with clearing/broker ops on settlement and corporate action timing.
FAQ
- Do specs change beyond expiry day? No—no other contract-spec changes have been announced alongside the shift.
- Will liquidity suffer? Typically stabilises after the first 2–3 cycles; temporary frictions are normal during calendar surgery.