A long straddle means buying a call and a put at the same strike and expiry, usually the at-the-money (ATM) strike. You pay both premiums up front. You do not need to guess the direction: a big move up makes the call valuable, a big move down makes the put valuable. What you need is size, a move larger than what you paid.
That makes the long straddle the natural trade before scheduled events whose outcome is uncertain: the RBI policy decision, the Union Budget, US inflation or Federal Reserve announcements, election results, and quarterly results for individual stocks. The economic calendar lists the dates.
Profit at expiry = value of the call + value of the put − straddle price paid
The catch: everybody knows the date
If a big move were a free bet, everyone would buy straddles the day before every event. They do try, and option sellers respond by asking for more. In the days before an event, implied volatility (IV), the expected size of moves built into option prices, rises. The straddle gets more expensive, so the move needed to profit gets bigger.
Once the news is out, the uncertainty is gone and IV drops sharply, often within minutes. This is the IV crush. A straddle can lose a large part of its value overnight even if the price moved, because the move was smaller than the drop in IV took away. The implied volatility guide explains IV in more detail.
A worked example: BANKNIFTY before RBI policy
BANKNIFTY is at 56,000 the afternoon before an RBI policy announcement, with a few days left to expiry. The 56,000 call costs ₹520 and the 56,000 put ₹480. The straddle costs ₹1,000. Assume a lot of 35 units for the arithmetic (lot sizes change; check the current figure on NSE): that is ₹35,000 per lot, and it is the maximum loss.
At expiry, only intrinsic value is left, so the payoff is easy to work out:
| BANKNIFTY at expiry | Call value | Put value | Profit per unit | Per lot of 35 |
|---|---|---|---|---|
| 54,500 | 0 | 1,500 | +500 | +₹17,500 |
| 55,000 | 0 | 1,000 | 0 | ₹0 |
| 55,500 | 0 | 500 | −500 | −₹17,500 |
| 56,000 | 0 | 0 | −1,000 | −₹35,000 |
| 56,500 | 500 | 0 | −500 | −₹17,500 |
| 57,000 | 1,000 | 0 | 0 | ₹0 |
| 57,500 | 1,500 | 0 | +500 | +₹17,500 |
The break-evens are 55,000 and 57,000: BANKNIFTY needs to move about 1.8% either way just to get the money back by expiry.
What happens the morning after
Most event traders do not hold to expiry; they sell the straddle soon after the announcement. Here the IV crush decides the result. Two illustrative mornings:
- A modest move. The RBI does what was expected and BANKNIFTY opens 400 points higher at 56,400. The call rises to about ₹650, but the put falls to about ₹260 and IV has dropped. The straddle is worth about ₹910: a loss of ₹90 per unit (₹3,150 per lot) even though the market moved.
- A surprise. The RBI surprises and BANKNIFTY jumps 1,300 points to 57,300. The call is worth about ₹1,420 (1,300 of intrinsic value plus some time value), the put about ₹110. The straddle is about ₹1,530: a profit of ₹530 per unit (₹18,550 per lot).
These figures are examples, not a pricing model, but the shape is typical: the straddle buyer is paid only when the outcome surprises the market.
Is the straddle cheap or expensive? A live check
The fairest test is to compare what the options expect with what usually happens. The box below shows BANKNIFTY's expected move from today's ATM straddle:
Ask whether past events of the same kind moved BANKNIFTY more or less than this range. If similar announcements usually moved it less, the straddle is priced for more drama than history suggests.
A second check is how high implied volatility is compared with its own past year, known as IV rank:
A high IV rank means options are already expensive relative to their usual level, which is common just before events. Buying straddles when IV rank is high leaves more room for a crush. The IV rank guide explains how it is calculated.
Company results: the same idea, stock by stock
For stocks, quarterly results are the biggest scheduled event. The straddle price the day before results tells you the move the market expects. ScreenerCharts records this and compares it with the actual move after the announcement on the results moves page. The results guide explains how to read that history. A stock that has moved less than its expected move on most past results is one where straddle buyers have usually overpaid; one that often moves more is the opposite. Past patterns can change, and a single quarter can break any pattern.
Timing the entry
- Earlier entry (several days before) can be cheaper, because IV has not yet fully risen, but you pay more time decay while waiting.
- Later entry (the day before) pays the highest IV but the least decay.
- Some traders buy early and sell before the event, aiming to profit from IV rising into the announcement rather than from the move itself. That avoids the crush, but it only works if IV actually rises enough to beat decay.
Whichever timing you choose, decide the exit before you enter: a time (for example, within the first hour after the announcement), a profit level, and a loss level. Event days are fast, and decisions made in the middle of a spike are rarely good ones.
Alternatives to the plain long straddle
- Long strangle. Buying an out-of-the-money call and put instead of the ATM pair costs less, so the maximum loss is smaller, but the move needed to profit is larger. It suits a view that the event could cause a very large move, not just a large one.
- Reverse iron butterfly. Buy the ATM straddle and sell a far call and far put against it. The sold wings lower the cost and the break-evens, but cap the profit. It suits a view that the move will be meaningful but not extreme.
- Doing nothing. If the expected move already looks generous compared with past events, there may be no edge in buying. Many experienced traders simply wait until after the announcement, when prices are calmer and the direction is known.
The opposite trade, selling the straddle into the event, collects the inflated premium but takes on the open-ended risk of a surprise. It is covered in the short straddle guide.
Risks and common mistakes
- Being right on the move and still losing. This is the IV crush, and it is the most common surprise for new straddle buyers.
- Buying the nearest expiry on the event day. Time decay is fastest there; a short delay in the reaction costs a lot.
- Treating it as low risk because the loss is limited. Losing the whole premium is a real, frequent outcome.
- Ignoring the spread. Bid-ask spreads widen around announcements, so entry and exit costs are higher than usual.
A long straddle is a fair trade only when you have a reason to think the move will be bigger than the market expects. Without that reason, it is a bet against professional sellers who price these events every month.