Introductory Context
"F&O transaction costs in India include STT, brokerage, SEBI charges, exchange transaction charges, GST, and stamp duty. For options buyers, the most significant trap is the higher STT on exercise versus on market sale. For active traders, total transaction costs meaningfully reduce net returns if not accounted for in target setting."
The Complete F&O Cost Structure
1. Securities Transaction Tax (STT)
• 0.0625% of premium paid. On 1 lot at ₹100 = ₹7,500 × 0.0625% = ₹4.69: Options buying.
• 0.0625% of premium received: Options selling (writing).
• 0.125% of intrinsic settlement value — double the trading rate. This is the STT trap: Options exercise (ITM expiry).
Example of exercise STT: your call expires ITM with intrinsic value of ₹300 per unit on 1 lot = ₹22,500 settlement. STT on exercise: ₹22,500 × 0.125% = ₹28.13. Had you sold before expiry at ₹300: ₹22,500 × 0.0625% = ₹14.06. Exercise STT is double the trading STT.
2. Brokerage
Flat-fee discount brokers (Zerodha, Upstox) charge ₹20 per executed order regardless of trade size. A 1-lot round trip = ₹40. A 10-lot round trip = still ₹40. This flat structure makes larger-lot trades proportionally cheaper per unit.
3. Exchange Transaction Charges, SEBI Charges, GST, Stamp Duty
NSE exchange charges approximately ₹1.85 per lakh of premium turnover. SEBI levies ₹10 per crore of turnover. GST at 18% applies to brokerage and exchange charges. Stamp duty on options buying is 0.003% of premium value. Individually small but cumulative across many trades.
Complete Cost Example — 1 Lot Nifty CE at ₹100 Premium
Buy order: STT ₹4.69 + Brokerage ₹20 + Exchange charges ₹0.14 + SEBI charges ₹0.08 + GST ₹3.63 + Stamp duty ₹0.23 ≈ ₹29. Sell order to close ≈ ₹26. Round-trip cost: approximately ₹55 on a premium of ₹7,500 — 0.73% round-trip cost. Small individually, significant across many trades over a year.
The STT Trap on Option Exercise
The most avoidable transaction cost mistake: holding an ITM option to expiry and allowing cash settlement, when selling before expiry generates the same economic outcome at half the STT cost.
If your option expires with ₹500 intrinsic value on 2 lots: settlement value = ₹500 × 75 × 2 = ₹75,000. STT on exercise = ₹93.75. Had you sold before expiry at ₹500: STT = ₹46.88. You paid ₹46.87 extra by holding to expiry. Multiply across multiple deep-ITM positions over a year and the cumulative STT drag is meaningful.
Always Exit Before Expiry
Exiting by selling is almost always preferable to holding to expiry — for three reasons: (1) You capture remaining time value as well as intrinsic value. (2) STT on sale is half the STT on exercise. (3) You eliminate overnight gap risk from the SOQ. Exit before expiry as the default — not as an afterthought.
Transaction Costs and Position Sizing
Transaction costs must factor into profit target setting. A ₹100 round-trip cost on a trade targeting ₹500 profit represents 20% of the target — high enough to matter. Always calculate transaction cost as a percentage of expected profit before entering any small-premium trade. Very short-duration, small-premium options (₹10–₹20 premium, 1–2 lots) are often structurally uneconomical: round-trip cost as a percentage of premium is very high.
Transaction costs are the rent you pay to participate in the market. They accumulate whether you are profitable or not. The trader who knows their exact transaction cost per trade — and who sets profit targets accounting for this cost — is already operating more professionally than most retail participants who treat brokerage as a background number they rarely examine.