Iron Butterfly Strategy on Nifty: Payoff, Breakevens, Wings and Adjustments

The iron butterfly strategy on Nifty is for the trader who thinks the index will sit close to one level until expiry and wants to collect option premium on that view, with the worst-case loss fixed before the trade even starts. You sell an at-the-money call and an at-the-money put, then buy a cheaper call above and a cheaper put below as protection. Below, we go through how the four legs fit together, work a full Nifty example with payoff, breakevens and maximum loss, compare the iron fly with a naked short straddle and an iron condor, and look at how traders exit or adjust. New to options? Start with our options trading for beginners in India guide.

Educational content only. Not investment advice. All index levels and premiums in the worked examples are hypothetical and chosen to keep the arithmetic easy to follow.

What is an iron butterfly strategy?

Investopedia defines an iron butterfly as a four-option trade that aims to profit when the underlying moves within a narrow range and implied volatility is falling. It uses two calls and two puts across three strike prices, all on the same expiry. Most traders just call it an “iron fly”.

The simplest way to picture it is two familiar trades stacked on top of each other. In the middle sits a short straddle: a call and a put sold at the same strike, near the current price. Around it sits a long strangle: a call bought above that middle strike and a put bought below it. Investopedia describes the iron butterfly in exactly these terms and points out that it looks like a short straddle with a long call and a long put added for protection.

You sell more premium than you buy, so the iron butterfly is a credit strategy. Money comes in when you open it, and the hope is that the options lose value so you keep as much of that credit as you can. The bought options, called the wings, are what turn an open-ended short straddle into a trade whose maximum loss is known up front.

The four legs of an iron butterfly

• Short at-the-money call: sold at the strike closest to where you expect Nifty to be at expiry. It brings in premium.
• Short at-the-money put: sold at the same middle strike. It also brings in premium.
• Long out-of-the-money call: bought at a strike above the middle strike. It caps your loss if Nifty rallies hard.
• Long out-of-the-money put: bought at a strike below the middle strike. It caps your loss if Nifty falls hard.

In a standard iron fly both wings sit the same distance from the middle strike, which makes the payoff symmetrical. That distance is the wing width. Along with the net credit, it decides almost everything about how the trade behaves.

Nifty options trade in lots. NSE’s F&O market lots file shows a lot size of 65 for Nifty 50 contracts, including the October, November and December 2026 series, so every rupee figure below is the points figure times 65. Lot sizes do get revised, so check the current file before you size a trade.

Iron butterfly formulas

For a symmetrical iron fly opened for a net credit, here are the values at expiry, in index points:

• Net credit = premium received on the short call and short put minus premium paid on the long call and long put.
• Maximum profit = net credit, earned only if Nifty settles exactly at the middle strike.
• Maximum loss = wing width minus net credit, suffered if Nifty settles at or beyond either wing.
• Upper breakeven = middle strike plus net credit.
• Lower breakeven = middle strike minus net credit.

Investopedia notes that the trade makes its maximum profit when the underlying closes exactly on the middle strike at expiry, loses value as the price drifts away in either direction, and hits its maximum loss once the price goes past the upper or lower strike. The formulas above are just that description turned into arithmetic.

Worked example: a Nifty iron butterfly

Say Nifty is at a hypothetical 23,000 and you expect it to hang around that level until the monthly expiry. You set up an iron fly with a 500-point wing width:

• Sell one lot of the 23,000 call at 220 points.
• Sell one lot of the 23,000 put at 200 points.
• Buy one lot of the 23,500 call at 60 points.
• Buy one lot of the 22,500 put at 55 points.

The two short options bring in 420 points and the two wings cost 115, leaving a net credit of 305 points, or ₹19,825 on one lot (305 × 65). Plug that into the formulas:

• Maximum profit: 305 points, or ₹19,825, if Nifty settles exactly at 23,000.
• Maximum loss: 500 minus 305, which is 195 points, or ₹12,675, if Nifty settles at or below 22,500 or at or above 23,500.
• Breakevens: 22,695 on the downside (23,000 minus 305) and 23,305 on the upside (23,000 plus 305).

At expiry, then, the trade makes money anywhere between 22,695 and 23,305. That’s a band of 610 points, about 2.7% of the 23,000 starting level. Outside it you lose, but never more than ₹12,675 before costs.

Payoff table at expiry

This table shows what each pair of options is worth at expiry and the net result on one lot, leaving out brokerage and charges.

The put and call columns show what each pair is worth to you at expiry: the short option’s loss, offset by the long option once Nifty goes past the wing. Add the 305-point credit and you get the net result. Look at how fast the profit fades. A 200-point move from 23,000 either way already cuts it from ₹19,825 to ₹6,825, and a 305-point move wipes it out.

An iron butterfly pays the most at a single point and less everywhere else. You are not betting that Nifty stays in a range so much as betting that it finishes very close to one strike.

Iron butterfly versus a naked short straddle

Now take the same short call and short put, minus the wings. You’d collect the full 420 points, or ₹27,300, and the breakevens would widen to 22,580 and 23,420. Looks better, until you check the tails. If Nifty settles at 22,000, the short put is 1,000 points against you and the straddle loses 580 points, or ₹37,700. At 24,000 the call side loses the same amount, and the loss keeps growing the further the index runs. With the wings on, the iron fly’s loss at either of those levels stays fixed at ₹12,675.

So the trade-off is plain enough. The wings cost 115 points of premium, which lowers the maximum profit and narrows the profit zone, but they put a hard ceiling on the loss. Investopedia counts this defined risk as one of the iron butterfly’s main advantages, since the long options cap the maximum loss if the price moves sharply away from the short strike.

Choosing the wing width

How far the wings sit from the middle strike changes the shape of the whole trade. Compare the 500-point fly above with a hypothetical 1,000-point fly that sells the same 23,000 straddle for 420 points but buys the 24,000 call at 15 points and the 22,000 put at 18 points:

Wider wings bring in more credit and push the breakevens out a little, but the maximum loss more than triples. Narrower wings cost more and leave a smaller credit, but the worst case shrinks a lot. No single width is the right one. Decide the maximum loss you can live with on the trade first, then pick the wing width that fits it. For a broader way to think about sizing, see our guide to risk management in trading.

Iron butterfly versus iron condor

The iron butterfly and the iron condor are close cousins. Investopedia defines an iron condor as a bear call spread plus a bull put spread, built from four out-of-the-money options on the same expiry. What separates them is where the short options sit:

• Iron butterfly: the short call and short put share one at-the-money strike. The credit is larger, but the maximum profit is earned only at that single strike and the profit zone is narrow.
• Iron condor: the short call and short put are at different out-of-the-money strikes. The credit is smaller, but the full profit is kept anywhere between the two short strikes, giving a wider, flatter profit zone.

If you have a precise idea of where Nifty will settle, the fly usually suits you better. If you only expect a range, the condor tends to fit. Our iron condor strategy on Nifty guide works through that trade the same way.

Volatility and time decay

The iron butterfly is a short-volatility trade. As Investopedia puts it, it profits from limited price movement and falling implied volatility. Since the position is net short option premium, a drop in implied volatility after you open it usually shrinks the options you sold more than the wings you bought, so the trade can gain even if Nifty hasn’t moved at all. When volatility jumps, the reverse happens, and you can be sitting on a mark-to-market loss before expiry even with Nifty still near the middle strike.

That’s why plenty of traders open iron flies when implied volatility is fairly high and likely to cool, say after a major event is out of the way, and stay away just before a scheduled event that could swing the index. If you expect a big move, you’d use the opposite structure, such as the long straddle.

The wings protect you from a large move, but they do not protect you from a rise in volatility. An iron fly can be under water early in its life even when the index has barely moved.

Exiting and adjusting an iron butterfly

Nobody says you have to hold an iron fly to expiry. Investopedia explains that you can close it early for a profit by selling back the long options and buying back the short ones, and most brokers let you do this as a single order. Suppose that a week before expiry Nifty is at 23,050 and the whole fly can be bought back for 150 points. Closing then locks in 155 points (305 minus 150), or ₹10,075 on one lot before costs, and takes the risk of a late move off the table.

Investopedia also notes that you can adjust an iron butterfly when conditions change, by rolling the options to different strikes or expiry dates. The usual adjustments are:

• Rolling the centre: if Nifty drifts well away from the middle strike, close the existing fly and open a new one centred on the new level. This books the loss on the old position, so treat it as a fresh trade, not a repair.
• Rolling to a later expiry: close the near-month fly and open one in a later expiry to collect more time value, accepting more time for the market to move against you.
• Closing the threatened side: buy back the short option that is in danger and keep the rest. This changes the risk profile, so recheck your maximum loss before doing it.

Every adjustment means four or more fresh orders. Investopedia stresses that commissions matter here because the strategy uses four options, so make sure brokerage, statutory charges and bid-ask spreads don’t eat most of the credit. And check the margin your broker blocks for the full four-leg position before you place the first order.

Expiry and settlement on Nifty

NSE’s Nifty 50 derivatives page says Nifty monthly options expire on the last Tuesday of the expiry month and weekly options every Tuesday, shifting to the previous trading day if that Tuesday is a trading holiday. Index F&O contracts are cash-settled, as Zerodha’s physical settlement policy notes, so a Nifty iron fly held to expiry settles in cash. No shares ever change hands.

That’s not how it works in Investopedia’s stock-based example, where a short put finishing in the money means the trader ends up buying the shares. You face the same risk in India if you build an iron fly on stock options. Zerodha’s policy says all stock F&O contracts on Indian exchanges require compulsory delivery, while out-of-the-money stock options expire worthless with no delivery obligation. So if you trade a stock iron fly, close it before expiry unless you’re ready for delivery.

Common mistakes with the iron butterfly

• Treating the credit as income: you keep the full credit only if Nifty settles exactly at the middle strike. Most of the time you keep part of it, and sometimes you take the maximum loss.
• Ignoring the loss-to-profit ratio: wide wings can make the credit look attractive while the maximum loss is several times larger.
• Opening before a big event: results, policy announcements and global shocks can move Nifty past a breakeven quickly and lift implied volatility at the same time.
• Legging in carelessly: putting on the four legs one at a time in a fast market can leave you holding an unhedged short option for a few minutes. Use a single multi-leg order where your broker allows it.
• Forgetting costs: four legs to open, and four more to close or adjust, add up quickly, especially on small credits.

For a wider look at how credit trades stack up against debit trades, read our explainer on debit vs credit spreads.

Key takeaways

• An iron butterfly strategy sells an at-the-money call and put on Nifty and buys an out-of-the-money call and put as wings, all with the same expiry.
• Maximum profit equals the net credit and is earned only at the middle strike. Maximum loss equals the wing width minus the net credit.
• The breakevens are the middle strike plus and minus the net credit, so the profit zone is often narrow.
• The trade benefits from falling implied volatility and is hurt by a sharp move or a jump in volatility.
• Nifty options are cash-settled. Stock options are physically settled, so close a stock iron fly before expiry unless you want delivery.

Disclaimer: This article is for information and education only and is not investment advice or a recommendation to buy or sell any security. Options involve risk and are not suitable for every investor. Consult a SEBI-registered investment adviser before making investment decisions.