NIFTY Lot Size Is Now 65, BANK NIFTY 30: What to Check
From the January 2026 contract series, the NIFTY 50 lot size is 65 units (down from 75) and the BANK NIFTY lot size is 30 (down from 35). If you run automated strategies, updating the lot count isn't enough: anything expressed in rupees rather than lots (stop-losses, targets, loss limits, sizing formulas) now behaves differently on the same settings.
The new lot sizes
- 65 NIFTY 50 lot (was 75)
- 30 BANK NIFTY lot (was 35)
- ₹65 per NIFTY point per lot (was ₹75)
- ₹30 per BANK NIFTY point per lot (was ₹35)
| Index | Old lot | New lot | Change |
|---|---|---|---|
| NIFTY 50 | 75 | 65 | −13.33% |
| NIFTY Bank | 35 | 30 | −14.29% |
NSE announced the revision in late November 2025, effective from the January 2026 series. December 2025 contracts ran to expiry under the old sizes; January 2026 contracts used the new ones. Lot sizes for other indices and for stocks were revised separately and change from time to time, so check NSE's current list for anything else you trade.
Two other changes matter for strategies built before late 2025: NSE expiries now fall on Tuesday, and BANK NIFTY has monthly expiries only (NIFTY is the only NSE index with weekly options). A strategy built around a weekly BANK NIFTY or a Thursday expiry needs the same review.
What the change means in rupees
At a NIFTY level around 26,000, one lot was about ₹19.5 lakh of notional exposure; it's now about ₹16.9 lakh. BANK NIFTY near 58,000 moved from about ₹20.3 lakh to ₹17.4 lakh per lot.
Two effects pull in opposite directions:
- Margin per lot fell, making each lot cheaper to hold and giving finer control over size. That was the intent.
- Profit and loss per point fell. A strategy sized for a certain rupee outcome now produces about 13% less on the same number of lots.
Ten checks for a strategy that was already running
The first two are obvious. The rest fail silently: the strategy keeps running and simply behaves differently from what you tested.
1. Is quantity set in lots or in units?
A strategy that sets quantity in lots picks up the new contract size automatically. One that sets an absolute unit count, or has 75 or 35 written into a formula, does not: it keeps asking for a quantity that no longer maps to whole contracts.
Open each deployed strategy and search the position legs and sizing logic for hard-coded numbers. Watch out for 65: it's the new NIFTY lot, but it may also be an old value for a different index in a strategy built earlier.
2. Your exposure changed even though your lot count didn't
Four NIFTY lots used to be 300 units. Now they are 260: 13% smaller, without you changing anything. And you can't get back exactly: five lots is 325 units, 8% more than before.
Decide deliberately: keep the lot count and accept lower exposure, or step up and accept more. If your sizing is based on capital, confirm the formula reads the current lot size, not a number captured when you built it.
3. Rupee stop-losses now trigger at a different point move
This is the most consequential item, and nothing on screen looks wrong.
The same stop-loss setting means something different after the lot change
- A ₹5,000 stop per lot used to be a 66.7-point NIFTY move. It's now 76.9 points. Your stop got wider, because each point costs less.
- A 60-point stop used to risk ₹4,500 per lot. It now risks ₹3,900. Your risk per trade fell, so a sizing model calibrated on the old number is now off.
The same applies to targets, trailing-stop triggers and trailing step sizes.
4. Strategy-level maximum loss and maximum profit
A daily maximum loss or profit lock in rupees now sits on a position that moves 13% less per point. In practice your circuit breaker is looser than before. Recalculate it from the new per-point value.
5. Cross-index hedge ratios drifted
NIFTY came down 13.33% and BANK NIFTY 14.29%. Any strategy balancing exposure between the two, such as a NIFTY position hedged with BANK NIFTY, now has a ratio about one percentage point off. Recompute it from the new unit counts rather than assuming the relationship held. If you pair NIFTY with other indices, check their current lot sizes on NSE and recompute those ratios too.
6. Multi-leg option structures and premium collected
Option sellers collect premium on fewer units, so income per lot falls in proportion. Restoring it means more contracts, and more costs.
If you use Overnight Protection, which buys a hedge before the session close and exits it the next trading day, check that the hedge quantity still matches the position it protects.
7. Backtests from before January 2026 describe a different contract
Backtests run before the change reflect the old lot size. Percentage results are broadly still informative; rupee P&L, rupee drawdowns and anything derived from them are not. Re-run the backtest before using it to justify a capital allocation, especially for strategies you haven't had a reason to open. See nine reasons your backtest doesn't match live trading.
8. External signals that send a quantity
If a strategy is driven by an external tool (a TradingView webhook, for example) that passes a quantity, check what it sends. A webhook sending a unit count instead of a lot count is a mis-sizing waiting to happen, and it won't announce itself. See TradingView integration.
9. If you publish strategies to the marketplace
Your subscribers' capital requirement changed, and so did the minimum capital to run one lot. If your strategy page states a minimum capital or rupee figures, update them. Subscribers running a multiplier are affected exactly as you are. See marketplace settings.
10. Re-validate Live Offline before you trust it
After adjusting a strategy, run it Live Offline (the strategy runs and records every trade, but nothing is sent to the exchange) and watch it take a few positions. Confirm the quantity that goes out matches your intent, and that stops trigger where you now expect, not where they used to.
- Search every deployed strategy for hard-coded 75, 35 or other old lot values.
- Decide lot count vs exposure for each strategy.
- Convert every rupee stop, target, trail and loss limit: keep rupees or keep points?
- Recompute cross-index hedge ratios.
- Check webhooks and external signals for unit quantities.
- Re-run backtests; update marketplace pages.
- Run Live Offline for a few sessions, then switch back to Live Auto.
Why lot sizes change at all
SEBI's framework sets bounds on the notional value of one derivatives contract. As an index rises, the value of one lot rises with it, and the exchange periodically trims the lot size to bring it back into range. NSE calculates revisions from the underlying's average closing price over a reference period.
The practical point: this will happen again. Make the ten checks a habit for every revision, rather than only updating the lot count.
Frequently asked questions
What is the NIFTY lot size now?
The NIFTY 50 lot size is 65 units from the January 2026 contract series. It was previously 75.
What is the BANK NIFTY lot size now?
The NIFTY Bank lot size is 30 units from the January 2026 contract series. It was previously 35.
When did the new lot sizes take effect?
From the January 2026 series, after the December 2025 contracts expired. Contracts that were already open in December 2025 kept the old size until they expired.
Do I need to change the lot size in my algo strategy manually?
If quantity is set in lots, the contract size updates automatically. If it is set in units, or the old lot size is typed into a sizing formula, you need to update it.
Does a lot size change affect my stop-loss?
Yes, if the stop is in rupees. A ₹5,000 per-lot stop was a 66.7-point NIFTY move with a 75 lot and is a 76.9-point move with a 65 lot, so the stop is effectively wider.
How much is one NIFTY point worth per lot now?
₹65 per NIFTY lot and ₹30 per BANK NIFTY lot, down from ₹75 and ₹35.
Are my old backtest results still valid?
Percentage results are broadly informative, but rupee figures such as per-trade profit, loss and drawdown reflect the old lot size. Re-run the backtest before using it to size capital.
Why does NSE change lot sizes?
To keep the notional value of one contract within the range SEBI's framework sets. As index levels rise, contract values rise, and the exchange periodically reduces the lot size.
