Introductory Context
"A put option gives the buyer the right to sell the underlying at the strike price before expiry. Profitable when prices fall below break-even (strike minus premium). Maximum loss is the premium paid. Maximum gain is substantial as the underlying falls. Break-even = strike price − premium paid. "
What a Put Option Gives You
When you buy a put option, you are purchasing the right — but not the obligation — to sell the underlying at the strike price before expiry. Think of it as a price floor. If you own a Nifty 24,000 PE and Nifty falls to 23,400, your put gives you the right to 'sell' Nifty at 24,000 — a price 600 points above where the market is trading. That 600-point gap is your intrinsic value.
In practice, Indian index puts are cash-settled — you do not actually sell the index. The intrinsic value at expiry is credited to your account in cash. The economic result is identical: the put option gains value proportional to how far the underlying has fallen below the strike.
A Complete Put Option Trade — Bank Nifty RBI Example
The Setup
Arjun, a trader in Bengaluru, believes the upcoming RBI MPC meeting will deliver a hawkish surprise — rates held with more aggressive-than-expected commentary. He expects Bank Nifty to fall. One week before the MPC meeting, Bank Nifty is at 50,800. He buys the 50,500 PE (slightly OTM) at ₹165 premium. Lot size: 30 units. Total cost: ₹165 × 30 = ₹4,950.
Break-Even
Break-even for a long put = Strike − Premium = 50,500 − 165 = 50,335. Bank Nifty must close below 50,335 at expiry for the trade to be profitable.
The Outcome
The MPC held rates with hawkish commentary. Bank Nifty fell 1,800 points. At expiry: Bank Nifty at 49,000. Intrinsic value = 50,500 − 49,000 = ₹1,500/unit. Value of 1 lot = ₹45,000. Net profit = ₹45,000 − ₹4,950 = ₹40,050. A return of over 800% on premium invested in one week — from a correct directional thesis on a high-probability catalyst.
The Put Payoff Structure
Long put: flat loss zone (−premium) when underlying stays above strike → kink at the strike → rising profit zone as underlying falls below break-even. Every point below break-even generates ₹1 per unit of profit (× lot size). This is the mirror image of the long call payoff — same structure, opposite direction.
The Put as Portfolio Insurance
Beyond directional trading, puts serve a critical role for equity investors: portfolio protection. Consider Vikram with ₹15 lakh in a Nifty 50 index fund worried about a sharp correction before the Union Budget. Instead of selling his fund — triggering capital gains tax — he buys Nifty ATM put options. If Nifty falls 5%, his index fund loses approximately ₹75,000 but his put options gain value, partially offsetting the loss. The premium paid is the insurance cost. If nothing bad happens, he loses only the premium — a defined, acceptable cost for peace of mind during an uncertain period.
Book 2 of the myfinversity Options Trading Series — Options Fundamentals: Calls, Puts and Premiums — covers the portfolio insurance application of put options in full depth, including how to calculate the correct number of lots to hedge a portfolio of any size, and the cost-effectiveness comparison of different hedging approaches.
Put Options and Portfolio Size
A common question: how many put option lots do I need to hedge my equity portfolio? A rough rule: divide your portfolio value by the Nifty lot value (Nifty level × lot size). For a ₹15 lakh portfolio with Nifty at 24,000: lot value = 24,000 × 75 = ₹18 lakh. You need approximately 1 lot of ATM puts for rough coverage. For precise hedging, you also need to account for your portfolio's beta relative to Nifty — covered in Module 19.