Options Selling: The Complete Guide to Short Premium on Indian Markets
Option sellers collect premium from option buyers in exchange for taking on risk. Professionally done, short premium is a disciplined income business with measurable probabilities; done amateurishly, it is an account-killer disguised as "easy money." This guide covers the mechanics of writing options, margin and margin-call risk, strike and expiry selection, adjustments, and the brutal honesty about tail risk.
Who Buys and Sells - and What Selling Means
Every option you buy comes from a seller on the other side of the trade. As a seller you are paid a premium now, and you keep it if the option expires worthless or buy it back cheaper earlier. You are short gamma and long theta: time works for you, but big directional moves work against you quickly.
Selling is not "writing a contract you will have to deliver"; on Indian exchanges it is an obligation settled by margin, and for index options it is always cash-settled.
The Income Business Model
- You receive premium upfront (today)
- You want the option to expire OTM (most do)
- You earn theta every day that passes
- You define the risk with the strike you choose and your stop
Historical note: the large majority of short-dated options in the US market expire worthless, and on Indian weekly NIFTY that DNA is similar, which is precisely why naked selling is tempting. Temptation is not strategy - the blow-ups come from the few expiries that don't play along.
Margin: Actually Understand It Before You Sell
Selling options requires margins computed in the SPAN system plus an exposure charge. The broker blocks margin at order time and can block more at end of day. Key facts:
- Naked short: margin roughly 15-35% of notional depending on distance from spot (NIFTY 1 lot at 24,600 is ~₹6.1L notional; margin several lakhs)
- Credit spreads: margin capped at the difference between strikes (e.g., 200 points wide = ~₹5,000 per NIFTY lot)
- Margin calls: if a position moves against you, the broker demands more funds. Ignoring a margin call leads to a square-off at exactly the worst time
Rule: never deploy more than 30-50% of available margin so the same positions can absorb mark-to-market swings without a call.
Strike Selection the Professional Way
Ditch "how many points OTM is safe?" in favour of delta-based selection:
- Choose your risk tolerance (conservative: 12-16 delta; aggressive: 20-25 delta)
- Select strikes at that delta from the live chain
- Verify the premium and distance in % terms, not points
At 15 delta a NIFTY short put might collect between 1.1% and 1.5% of the future value in premium per monthly cycle. If that doesn't clear your cost hurdle, the strategy needs more cycles, not more risk per cycle.
Expiry Selection: Weekly vs Monthly Premium
Weekly expiries give the fastest theta but the scariest gamma. Monthly contracts give better risk-to-reward and more time to adjust. Most disciplined sellers avoid naked weeklies until they have proven they can manage monthly shorts for a year. Weeklies belong, if anywhere, in defined-risk spread form.
Adjustment Playbook (Before You Need It)
- Book profit at 40-50%: closing a sold option that has decayed by half returns capital and avoids the final-theta drama
- Roll a tested strike: buy back the short near the money, sell a further OTM strike in the same or next expiry, and collect more credit
- Convert to a spread: when a naked short approaches danger, buy a protective further-OTM option and cap the catastrophe
- Close and wait: sometimes the clear-eyed decision is to take the risk off the table entirely and wait for a calmer market
The Tail-Risk Honesty Section
Premium selling returns a lot of small profits punctuated by rare large losses. The arithmetic only works if the few large losses are truly capped and not career-ending. In February 2020 and on sharp panic days, NIFTY fell 5-10% in a session; sellers who were "safe" at the previous close discovered the gap had blown straight through their strikes. This is why experienced sellers always keep a defined-risk shape (spreads) or a strict stop, and never sell naked size they cannot lose in one bad session.
SEBI Disclaimer
Options trading involves substantial risk including losses beyond your premium and margin. This article is educational only and is not investment advice. Selling options is complex and is not recommended for beginners without professional guidance.
