Core conceptIntermediate

Assignment

Assignment is the process by which an option seller (writer) is required to fulfil the obligations of an option that a holder has exercised — the mirror image of exercise, and largely automatic at expiry in India.

Quick Answer

Assignment falls on option sellers when a buyer's in-the-money option is auto-exercised at Indian expiry, and the clearing corporation allocates the resulting obligation systematically by settlement price rather than by broker choice. A seller short a Nifty 25,000 call that settles 90 points in-the-money pays 90×65 = ₹5,850 in cash, while an assigned stock-option seller must deliver or buy shares.

Definition of Assignment

Assignment is the process by which an option seller must fulfil the obligations of an option a holder has exercised, the mirror image of exercise, automatic at expiry in India.

Key takeaways on Assignment

  • Assignment is the seller's side of exercise — being required to fulfil an exercised option.
  • At Indian expiry, in-the-money short options are assigned automatically (cash for index, delivery for stocks).
  • European style means assignment only at expiry, but any in-the-money short will be assigned.

Assignment at a glance

Assignment — key facts at a glance
DefinitionSeller's obligation when buyer exercises an in-the-money option
TriggerAuto-exercise of ITM options at expiry
Allocation methodSystematic, settlement-price driven (not random/broker pro-rata)
Index obligationCash settlement of intrinsic value, netted against premium
Stock obligationPhysical delivery — call seller delivers shares, put seller buys
TimingEuropean style — only at expiry, no early assignment
ExampleNifty 25,000 CE 90pts ITM = 90×65 = ₹5,850 (illustrative)

Assignment in simple words

When you sell (write) an option, you take on an obligation: if the buyer exercises, you must settle. Assignment is being 'called upon' to meet that obligation. At Indian expiry, when in-the-money options are auto-exercised, the exchange assigns those obligations to sellers — who then pay the cash difference (index options) or deliver/receive shares (stock options).

Why Assignment matters

Assignment is what makes option selling meaningful: it enforces the seller's obligation so the buyer's right has value. Understanding assignment tells a seller exactly what they can be forced to do, and when.

Assignment: visual explanation

When an in-the-money option is exercised, the exchange assigns the obligation to an option seller.

At expirysettlement price fixedIn-the-money?Index option → cashdifference paid in cashStock option → deliveryshares delivered & paidOut-of-the-moneyexpires worthless, ₹0NoYes

Assignment: professional explanation

How assignment works at expiry

When in-the-money options are auto-exercised at expiry, the clearing corporation assigns the corresponding obligations to sellers of those options. For index options this is a cash obligation equal to the intrinsic value; for stock options it is a delivery obligation. Assignment at Indian expiry is systematic, not random broker choice, because it is settlement-price driven.

The delivery risk for stock-option sellers

A seller of a stock option that finishes in-the-money is assigned a delivery obligation: a call seller must deliver shares, a put seller must buy them. This can require large funds or a stock inventory on settlement day and is the single biggest expiry surprise for retail sellers of stock options.

European style means assignment only at expiry

Because Indian options are European, assignment can only occur at expiry, never early. Sellers therefore do not face surprise mid-life assignment — but they must manage the expiry outcome, since any in-the-money short option will be assigned.

Assignment in practice (Nifty / Bank Nifty)

Illustrative — Nifty spot 25,000, lot size 65

You sold a Nifty 25,000 CE and the index settles at 25,090. Your short call is in-the-money by 90 points, so you are assigned: you pay 90 × 65 = ₹5,850 in cash (offset against the premium you collected). No shares are involved because index options are cash-settled.

Had you instead sold an in-the-money HDFC Bank call into expiry, assignment would mean physically delivering HDFC Bank shares — needing the stock or the funds to buy it — a far larger obligation than the netted index cash example.

Advantages of Assignment

  • Assignment enforces the seller's obligation, which is what gives options their value.
  • European style means no surprise early assignment — only at expiry.
  • Index-option assignment is a simple cash settlement, netted against premium.

Limitations of Assignment

  • Stock-option assignment creates a physical-delivery obligation that can be large and costly.
  • Any in-the-money short option will be assigned — sellers cannot avoid it once at expiry in-the-money.
  • Assignment can turn a small premium into a large settlement obligation if the move was big.

Why Assignment matters in practice

  • As a seller, know that any short option in-the-money at expiry will be assigned.
  • For stock options, manage or close short positions before expiry to avoid unwanted delivery.
  • Keep funds ready for the settlement obligation that assignment can create.

Common misconceptions about Assignment

  • Misconception: Assignment at Indian expiry is random.

    Reality: For Indian exchange-settled expiry, assignment follows the settlement price systematically. In markets with broker-level allocation, a random or pro-rata method may be used, but Indian expiry assignment is settlement-driven.

Common mistakes with Assignment

  • Selling options and forgetting that an in-the-money finish means guaranteed assignment.
  • Ignoring the delivery consequences of being assigned on a stock option.
  • Assuming assignment can happen early and mismanaging European-style positions.

How professionals treat Assignment

Professionals who sell options plan for assignment from the outset: they track which shorts risk finishing in-the-money, close or roll stock-option shorts before expiry to avoid delivery, and fund the potential cash obligation on index shorts. Assignment is a known, managed part of their process, never a shock.

Assignment: frequently asked questions

How does assignment happen in India?

At expiry, in-the-money options are auto-exercised and the clearing corporation assigns the resulting obligations to sellers based on the settlement price. It is systematic, not a random broker decision.

Can I be assigned before expiry in India?

No. Indian options are European-style, so assignment can only occur at expiry. There is no early assignment risk during the contract's life.

What happens if I'm assigned on an index option?

You settle the intrinsic value in cash — the difference between the strike and the final settlement price — netted against the premium you received. No shares are involved.

What happens if I'm assigned on a stock option?

You face a physical-delivery obligation: a call seller delivers shares, a put seller buys them, over the equity settlement cycle. This can require substantial funds or stock.

How can I avoid assignment?

Close (buy back) your short option before the expiry close so you no longer hold it at settlement. Any short option in-the-money at expiry will otherwise be assigned.

Does assignment cost extra?

Being assigned corresponds to the option being exercised, which attracts STT on the intrinsic value and, for stocks, delivery-related costs — generally more than simply closing the position beforehand.

Who gets assigned when an option is exercised?

A seller of that option series is assigned. At Indian expiry the clearing corporation assigns in-the-money short positions their obligations automatically.

Can assignment cause a loss bigger than the premium?

Yes. If the underlying moved far beyond the strike, the settlement obligation from assignment can far exceed the premium collected — a key risk of selling options.

People also ask about Assignment

Questions best answered by their own dedicated pages:

Sources & references for Assignment

Published 10 July 2026. Educational content only — not investment advice. Exchange rules change; verify current conventions on NSE/BSE.

Educational content only — not investment advice. Examples use illustrative numbers and current exchange conventions that may change. Options and futures involve substantial risk. See our Risk Disclosure and SEBI Disclaimer.