Imagine you are an analyst monitoring a Nifty 50 futures contract during the final hour of trading on expiration Thursday. You notice that the spot index is trading at 22,050, while the near-month futures contract is flickering between 22,051 and 22,052. A junior associate asks why the futures price does not trade significantly higher, given that the contract had a noticeable ‘cost of carry’ premium throughout the month.
This observation is the perfect entry point to discuss the inevitability of price convergence—the mechanism that forces the futures price to lock into the spot price as the delivery date arrives.
The logic of convergence is rooted in the absence of time. A futures contract is essentially a promise to deliver an asset at a future date, and the ‘premium’ or ‘discount’ in the futures price over the spot price represents the cost of holding that asset until the maturity date. As the maturity date approaches, the time period—and thus the cost of carry—shrinks toward zero.
On the exact moment of expiry, the futures contract effectively becomes a spot transaction, as the delivery or settlement is immediate. If the futures price were even slightly different from the spot price at that precise moment, an arbitrageur could purchase the cheaper asset and sell the more expensive one, capturing a risk-free profit until the prices align.
For an investment advisor, understanding this concept is critical when calculating hedging effectiveness. If you are hedging a portfolio of equity shares using futures, you must account for the basis risk—the difference between the spot price of your holdings and the futures price. Early in the contract life, the basis is dictated by interest rates and dividend yields. As you move closer to expiration, the basis must narrow.
Ignoring this expected path of convergence can lead to significant miscalculations in hedge performance or errors when unwinding positions in a systematic trading strategy.
Consider a case where a portfolio manager holds a large basket of stocks and sells futures to hedge against a short-term market downturn.
If the manager expects the basis to remain wide until the very end, they may be surprised to find their hedging ‘gain’ eroding as the basis shrinks, a phenomenon known as ‘convergence to spot.’ By anticipating this mechanical narrowing, the advisor can better time the exit of both the spot and futures positions, ensuring that they do not inadvertently lock in losses due to a failure to account for the vanishing cost of carry.
Nuance
Check Your Understanding
An analyst is tracking a Nifty futures contract two days before expiration. The spot price is Rs. 19,500 and the futures price is Rs. 19,505. Which of the following best describes the expected behavior of the futures price as it approaches the final settlement hour?
Which of the following conditions is most likely to cause a futures contract to trade at a price significantly different from the spot price on the actual day of expiration?
This is a companion read for Section 10.8 — Derivative markets, products and strategies from PASS Investment Adviser (Level 1) by Akhilesh Gururani, available on Amazon Kindle.
Copyright © 2026 HABSG Consulting