What you will learn in this lesson
- Understand why a Futures price usually differs from the underlying's spot price
- Learn what "cost of carry" means, and its main components
- Understand the difference between Futures trading at a premium vs a discount
- Learn why the Futures-spot gap narrows to zero exactly at expiry
- Be able to interpret what a widening or narrowing premium/discount might suggest
You’ve probably already noticed something if you completed this lesson’s exercises earlier: the Futures price and the spot price of the same underlying aren’t usually identical. This lesson explains exactly why — and closes out your Futures foundation before we move into Options.
Why Futures Price Differs From Spot Price
A Futures contract’s price theoretically reflects the underlying’s current spot price, adjusted for the cost of “carrying” (holding) that position until the contract’s expiry.
This adjustment is called the cost of carry, and it’s mainly driven by:
- Interest cost — theoretically, buying the underlying today and holding it until the Futures expiry ties up capital, which has a cost (roughly reflecting prevailing interest rates).
- Dividends (for stock Futures) — if you held the actual stock, you’d receive any dividends paid during that period. Since a Futures holder doesn’t directly receive those dividends, expected dividends are subtracted from the cost of carry, reducing the premium.
Theoretical Futures Price ≈ Spot Price + Cost of Carry
(Interest Cost − Expected Dividends)This is a simplified version of the actual formula used in practice, but it captures the core logic clearly enough for this stage of the course.
Premium and Discount: Two Sides of the Same Idea
- Premium — the Futures price is higher than the spot price. This is the more common scenario, consistent with a positive cost of carry (interest cost typically outweighing dividend offset).
- Discount — the Futures price is lower than the spot price. Less common under standard assumptions, but can happen, particularly during strongly bearish sentiment or other market-specific dynamics.
| Scenario | Futures Price vs Spot | Common Interpretation |
|---|---|---|
| Premium | Futures > Spot | Standard cost-of-carry dynamic; can also reflect bullish demand |
| Discount | Futures < Spot | Less common; can reflect bearish sentiment or specific supply/demand factors |
Convergence: Why the Gap Must Close by Expiry
Here’s the elegant part: the Futures price and spot price must converge — become equal or nearly equal — exactly at expiry.
Why? Because cost of carry is fundamentally about the cost of holding a position over remaining time. As the time remaining to expiry shrinks toward zero, so does the cost-of-carry component — leaving the Futures price with nothing left to differ from spot by.
Time to Expiry: Long Medium Very Short Zero (Expiry)
Futures vs Spot: Larger gap → Smaller gap → Very small gap → Converged (≈ equal)If the two prices didn’t converge, it would create a persistent, exploitable price mismatch — professional traders (through an activity called arbitrage) would act on it, and their trading activity itself would help correct the mismatch, pushing prices back toward the expected relationship.
Real-Life Example: Watching Convergence Happen
Suppose, at the start of a monthly expiry cycle, Nifty 50 Futures trades at a premium of 60 points above spot. As the days pass, assuming no major new market-moving events, you’d typically observe that premium gradually shrink — perhaps down to 40 points with two weeks left, 15 points with a few days left, and effectively 0 by the final settlement moment on expiry day. This isn’t a coincidence or manipulation — it’s the direct, structural result of cost of carry shrinking as time-to-expiry shrinks.
Analogy: A Pre-Paid Taxi Booking Fee That Shrinks Over Time
Imagine a taxi service that lets you lock in today’s fare for a ride scheduled far in the future, charging a small “holding fee” on top of today’s fare to cover their cost of reserving that car and driver for you over that time period.
- If you book a ride 3 months in advance, the holding fee is relatively larger — they’re committing resources for a long time.
- If you book the same ride just 1 day in advance, the holding fee is much smaller — barely any commitment period involved.
- On the day of the ride itself, there’s effectively no “holding fee” left — the booked fare and the “spot” fare for that exact moment are the same thing.
This mirrors exactly how a Futures premium behaves relative to spot: larger with more time remaining, shrinking as expiry approaches, and fully gone at the moment of expiry itself.
Common Beginner Mistakes
- Assuming Futures price should always exactly equal spot price. The cost-of-carry relationship explains why they normally differ, and by how much.
- Confusing “Futures premium” with “Options premium.” These are two entirely different concepts that happen to share a word — don’t let the shared terminology cause confusion later, in Module 5 onward.
- Treating a widening or narrowing premium as a reliable, standalone trading signal. It’s one data point among several, not a guaranteed predictor of future price direction.
- Ignoring convergence when holding a position close to expiry. If you’re long and the premium is shrinking (even with spot flat), your Futures position’s price will still drift down toward spot — a dynamic distinct from spot price movement itself.
Practical Tips
- When checking a Futures contract’s price, get in the habit of also checking the current spot price of the same underlying — the gap (premium or discount) is meaningful context, not noise.
- Don’t panic if a Futures price seems to “underperform” spot as expiry nears — convergence is expected, structural behavior, not necessarily a bearish signal.
- If you plan to hold a Futures position for an extended period, understand that near-expiry convergence will affect your position’s price, independent of whether the underlying itself moves.
Practical Exercise
- Check the current spot price of Nifty 50, and the current price of its near month Futures contract, at the same moment. Calculate the difference in points and in percentage terms — is the Futures price higher (premium) or lower (discount) than spot?
- Repeat the same check a few days later. Has the gap between spot and Futures widened, narrowed, or stayed roughly the same as expiry approaches? Note your observation — this builds direct intuition for the "convergence to spot" concept covered in this lesson.
Mini Quiz
1. What is "cost of carry" in the context of Futures pricing?
Cost of carry represents the net cost of theoretically holding the underlying asset until expiry, primarily reflecting the interest cost of capital tied up over that period (minus any dividends received, for stocks).
2. If a stock's Futures price is trading above its current spot price, what is this called?
When the Futures price is higher than the spot price, the Futures contract is said to be trading at a "premium" to spot.
3. What typically happens to the gap between a Futures price and the spot price as expiry approaches?
As expiry approaches, the Futures price and spot price converge — at expiry itself, they must be equal (or extremely close), since the "time left to carry" the position shrinks to zero.
4. Which of these is a component that typically influences cost of carry for a stock Futures contract?
Cost of carry for stock Futures is mainly driven by interest cost (the "carry" cost of capital) offset by any dividends expected during the holding period, since dividends reduce the practical cost of holding the position.
5. Can a Futures contract trade at a discount to spot?
While a premium (Futures above spot) is more common under standard cost-of-carry assumptions, a discount (Futures below spot) can occur, often reflecting strongly bearish sentiment or other market-specific factors.
6. Why does the Futures price NOT simply equal the spot price at all times?
The Futures price theoretically reflects spot price adjusted for cost of carry over the remaining time to expiry — a real, time-dependent relationship, not two unrelated numbers.
7. If you're holding a long Futures position and the premium to spot shrinks over time (even if spot itself doesn't move), what happens to your Futures position's price?
As the premium narrows (convergence toward expiry), the Futures price moves toward the spot price, all else being equal — a dynamic separate from, but often alongside, actual spot price movement.
Frequently Asked Questions
Do I need to calculate cost of carry manually before every Futures trade?
No — the Futures price you see quoted on your broker's app already reflects the market's current, real-time cost-of-carry pricing (plus supply/demand for that specific contract). Understanding the concept helps you interpret why the price behaves the way it does, but you don't need to independently calculate it for everyday trading decisions.
Why do dividends reduce the cost of carry for stock Futures?
If you held the actual stock (instead of a Futures contract) during the holding period, you'd receive any dividends the company pays. Since a Futures holder doesn't receive those dividends directly, expected dividends are subtracted from the theoretical cost of carry — effectively reducing the premium a stock Futures contract would otherwise trade at.
Is the "premium" in Futures pricing the same as the "premium" paid for an Option?
No — this is a common point of confusion, since both use the word "premium." A Futures premium refers to the Futures price being above the spot price. An Option premium (covered starting Module 5) refers to the price paid to buy an Option contract — a completely different concept, despite the shared word.
What does it mean if a stock's Futures is trading at an unusually large premium to spot?
It can suggest the market has bullish expectations, elevated demand for that specific Futures contract, or simply reflects a higher cost-of-carry environment (e.g., higher prevailing interest rates). It's one data point among many, not a standalone trading signal by itself.
Why does the Futures price have to converge exactly to the spot price at expiry?
Because at expiry, there's no remaining time left to "carry" the position — the cost-of-carry component that creates the premium/discount shrinks to zero as the time-to-expiry shrinks to zero. If they didn't converge, market participants could exploit the price gap for near risk-free profit until it closed (a concept called arbitrage), which market forces naturally correct.
What is "arbitrage," briefly, in relation to Futures-spot mismatches?
Arbitrage means simultaneously buying and selling related instruments (like spot and Futures of the same underlying) to profit from a temporary, unjustified price mismatch, with the actions of arbitrageurs helping to correct that mismatch quickly. It's generally a professional/institutional activity requiring significant speed and capital, not something typical retail beginners engage in directly.
Does cost of carry apply the same way to index Futures as it does to stock Futures?
The same core concept applies — interest cost minus expected dividends from the index's constituent companies — though the specific calculation for an index involves aggregating the expected dividend yield across all constituent stocks, rather than a single company's dividend.
Can I use the Futures premium/discount as a standalone trading signal?
It's generally considered one input among many, rather than a standalone, reliable signal — professional traders often look at premium/discount alongside Open Interest, volume, and broader market context (covered in later modules) rather than in isolation.
Does a widening premium mean the price will definitely keep rising?
No. A widening premium reflects current market pricing dynamics (demand, sentiment, cost of carry), not a guarantee of future direction. Treating any single indicator as a certain predictor of future price movement is a common and risky beginner mistake.
How does understanding Futures pricing help with Options later in this course?
Options pricing (covered from Module 5 onward) also involves the underlying's price relationship, along with additional factors like time value and volatility (Implied Volatility, Module 11). Understanding how Futures price relates to spot builds useful intuition for how "derived" pricing works before Options introduce more complexity on top of that same foundation.
Glossary
Key Takeaways
- A Futures price typically differs from the spot price due to "cost of carry" — mainly the interest cost of capital, offset by expected dividends for stock Futures.
- When Futures trades above spot, it's called a premium; when below spot, a discount.
- The gap between Futures and spot price narrows as expiry approaches, converging to (near) zero exactly at expiry.
- A Futures "premium" is a different concept from an Options "premium" — the shared word describes two unrelated things.
- Premium/discount reflects current cost-of-carry and market dynamics, not a standalone, reliable predictor of future price direction.
- You don't need to manually calculate cost of carry for everyday trading — the quoted Futures price already reflects it — but understanding the concept helps interpret price behavior.
Conclusion
Futures pricing isn't arbitrary — it's a logical, time-dependent relationship anchored to the spot price, shaped by cost of carry, and guaranteed to converge exactly at expiry. This closes out Module 4, and with it, your complete foundational understanding of Futures contracts: what they are, how to trade them practically, and how they're priced. From here, Module 5 begins the Options side of this course — starting with what Options are, at the same first-principles depth we've just applied to Futures.