Rollover in Indian Futures: Spreads, Percentages and Costs

What Rollover Actually Means

Rollover is the process of carrying a futures contract position forward from the contract that is about to expire into a later contract. You do it by squaring off (closing) the near month position and at the same time opening the same direction position in the next month or a further series. If you are long one lot of Bank Nifty June futures and you still want to stay long into July, you sell your June lot and buy a July lot. Your directional view survives the expiry; only the contract month changes.

Rollover exists because every futures contract has a fixed last trading day. In India that is the last Tuesday of the expiry month for NSE monthly contracts (shifted to the previous trading day if that Tuesday is a holiday). At expiry an index future is cash settled against the closing spot value, and a stock future is settled by physical delivery of shares if you do not close it. A trader who wants to avoid forced settlement, avoid delivery obligations, and keep a longer term view must roll the position before that last session.

Rollover is not a single special order type on most retail platforms. It is two ordinary trades: an exit in the expiring series and an entry in the next series. Some brokers offer a spread or calendar order that executes both legs together to reduce the risk of the market moving between the two fills, but the economics are the same. You are always paying the price difference between the two contracts plus the transaction charges on both legs.

How Rollover Works on NSE Expiry

Indian monthly derivatives on the NSE expire on the last Tuesday of the month. The next month contract trades alongside the near month for the whole period, so on any given day you can see the June, July and August Nifty futures quoted at the same time. As expiry nears, traders gradually shift their open interest from the expiring series to the next one. This shifting is the rollover, and it clusters into the final three trading sessions before expiry, with the heaviest activity on expiry day itself.

The price gap between the two contracts is driven by the cost of carry. A further dated future usually trades above spot because holding a position for longer carries an implied interest cost, partly offset by expected dividends in the case of stock and index futures. So in a normal market the next month future trades at a small premium to the near month future. That premium is what you effectively pay to roll a long position forward, and it is what you receive to roll a short position forward.

When the next month trades at a premium to the near month, the market is in contango, which is the usual state. When the next month trades below the near month, the market is in backwardation, which often appears around heavy dividend dates or when there is strong selling pressure and demand to stay short. Backwardation makes rolling a long position cheaper or even profitable, and makes rolling a short more expensive.

Worked Example: Rolling One Bank Nifty Lot With Real Spread Cost

These numbers are illustrative and use realistic 2026 levels and current charge rates. Suppose on expiry Wednesday a trader is long 1 lot of Bank Nifty June futures. The Bank Nifty lot size is 30. The June future is trading at 52,000 and the July future at 52,180. The trader wants to stay long into July, so they roll: sell June at 52,000 and buy July at 52,180.

The rollover spread is 52,180 minus 52,000, which is 180 points. Per lot that spread costs 180 points times 15, which is Rs 2,700. That Rs 2,700 is the headline cost of staying long, before any brokerage or taxes. It is the price you pay for time, and you only get it back if Bank Nifty rises by at least 180 points more than it otherwise needed to.

Now add the transaction charges on both legs. Each leg has a notional value of roughly Rs 7.8 lakh (52,000 times 15 is 7,80,000 for the sell leg, and 52,180 times 15 is 7,82,700 for the buy leg). On a typical discount broker charging a flat Rs 20 per executed order, the brokerage is Rs 20 times 2 orders, which is Rs 40. The other statutory charges apply per leg, as shown below.

So rolling one Bank Nifty lot forward in this example costs about Rs 2,956, of which Rs 2,700 is the spread and roughly Rs 256 is brokerage and statutory charges. The pure transaction cost of the roll, ignoring the spread, is small relative to the position, but the spread is the part that quietly eats into a long position month after month. A trader who rolls a long Bank Nifty lot every month at a 180 point premium is paying roughly Rs 2,700 in spread per roll, which over a year is meaningfully more than the slab tax most people first worry about.

Rollover Percentage: What The Numbers Mean

Rollover percentage measures how much of the expiring open interest moved into the next series rather than being closed out. A simple way exchanges and brokers compute it is: next series open interest divided by the sum of next series plus expiring series open interest, measured around expiry. A reading of 80 percent means 80 percent of the positions that existed were carried forward and only 20 percent were squared off and left the market.

Typical ranges in the Indian market are useful to memorise. Nifty futures usually roll in the 75 to 80 percent band. Bank Nifty, being more leveraged and trader heavy, often rolls higher, in the 80 to 90 percent band. Individual stock futures vary widely, from 60 percent on quieter names to over 90 percent on highly active counters. What matters is not the absolute number alone but how it compares to that stock or index three month average, which most broker research desks publish each expiry.

Direction matters too. A high rollover combined with a rising price and rising cost of carry usually means longs are confidently carrying forward. A high rollover with falling price often means shorts are carrying forward, which is a bearish signal even though the headline rollover percentage looks healthy. Always read rollover percentage together with price action and whether the roll is happening at a premium or a discount.

The Real Costs You Pay To Roll

There are four cost buckets in any roll. The first and largest is the calendar spread, the price difference between the two contracts, which we showed above as Rs 2,700 on the Bank Nifty example. The second is brokerage, which on most discount brokers is a flat fee per order, around Rs 20, so two orders cost about Rs 40 regardless of position size. The third is statutory and exchange charges: securities transaction tax, exchange transaction charges, the SEBI turnover fee, stamp duty and GST. The fourth is slippage, the gap between the price you expected and the price you actually got.

The single tax that surprises new traders most is the securities transaction tax on futures. STT on a futures sell is 0.02 percent of the sell side contract value, charged only on the sell leg. On the Rs 7.8 lakh sell leg in our example that is Rs 156. Because a roll always involves one sell and one buy, you pay STT on the sell leg of the roll, and you will pay it again next month when you eventually exit. None of these charges depend on whether you make a profit; they are paid on turnover.

• Calendar spread: the price gap between near and next month, by far the biggest cost on index rolls.
• Brokerage: typically flat Rs 20 per order on discount brokers, so about Rs 40 for the two roll legs.
• STT: 0.02 percent on the futures sell leg value only.
• Exchange transaction charge, SEBI fee and stamp duty: tiny per leg but real, and applied on both legs.
• GST: 18 percent on brokerage plus exchange and SEBI charges.
• Slippage: worse on illiquid stock futures and on the last minutes of expiry day.

How Rollover Is Taxed In India

This is where many traders get it wrong. Profit or loss from futures and options, including the legs of a rollover, is treated as non speculative business income under Indian income tax rules. It is not capital gains. So the capital gains rates that apply to delivery equity, namely short term capital gains of 20 percent and long term capital gains of 12.5 percent above Rs 1.25 lakh, do not apply to your F&O rollover trades. Your F&O profit is added to your other income and taxed at your applicable slab rate.

Because it is business income, you can deduct related expenses such as brokerage, STT, exchange charges, internet and advisory costs against your F&O profit. You report it under the business head, not the capital gains head, and depending on turnover and profit you may fall under presumptive taxation or be required to maintain books and, in some cases, get a tax audit. STT paid on F&O is now allowed as a business expense, which is different from the old treatment for capital gains, so keep your contract notes for every leg of every roll.

Common Rollover Mistakes To Avoid

The most expensive mistake is treating rollover as automatic. Rolling a losing position forward simply because you do not want to book the loss is rarely a strategy; it just adds another spread and another set of charges to a position your original thesis no longer supports. Decide whether you would open the position fresh today. If the answer is no, the roll is just denial with a cost attached.

The second common error is ignoring liquidity in the far month. The near month is always the most liquid; the next month is liquid for index futures but can be thin for many stock futures, leading to wide bid ask spreads and real slippage on the entry leg. Rolling too late, into the final minutes of expiry day, also forces you into whatever spread the market is offering at that moment. Rolling a day or two early, when both contracts are liquid, usually gets a tighter spread.

• Rolling a losing trade only to defer booking the loss, adding cost without conviction.
• Ignoring the calendar spread and assuming the roll is free because brokerage is small.
• Rolling into a thin far month stock future and eating slippage on a wide spread.
• Leaving the roll to the last minutes of expiry day instead of rolling when liquidity is best.
• Forgetting physical delivery risk on stock futures left open past expiry.

SEBI Rules And Expiry Mechanics

The derivatives market is regulated by the Securities and Exchange Board of India (SEBI), which sets contract specifications, margin requirements and settlement rules. Monthly index and stock futures on the NSE expire on the last Tuesday of the month. SEBI has also rationalised weekly expiries so that each exchange offers weekly options on only one benchmark index, which affects how traders hedge around the monthly roll. Stock futures are settled by physical delivery if held to expiry, which is why traders who do not want to take or give delivery must square off or roll before the last session.

Margin matters during rollover because for a short window you may briefly hold or be exposed to both legs. Using a broker calendar spread order can reduce the margin and the execution risk of being filled on one leg but not the other. SEBI peak margin and upfront margin rules mean you must have sufficient margin for the new month position before the roll completes, so check your available margin before expiry rather than discovering a shortfall at the last minute.

Reading Rollover Data Before You Trade

Treat rollover statistics as one input among several, not a signal on their own. Combine the rollover percentage with the price trend, the cost of carry, and the open interest change. A constructive long setup might show rollover above the three month average, price holding above a key level, and the next month at a normal premium. A warning setup might show high rollover with falling price and a widening discount, which can mean aggressive shorts are carrying forward. The data is published by NSE and by most broker research desks each expiry week.

Sources And Further Reading

For authoritative data and contract specifications, refer to NSE India, the NSE Option Chain and Zerodha Varsity. STT, exchange charges, stamp duty and lot sizes change from time to time, so always confirm the current rates, lot sizes and expiry calendar on the official source or your broker before you place a roll. The rupee figures in this guide are illustrative and not a forecast or a promise of returns.

Sources and Further Reading

For authoritative data and further reading on this topic, refer to NSE India, NSE Option Chain and Zerodha Varsity. Always confirm current rules, rates and contract specifications on the official source before you trade.