Fundamentals

Basis Risk: Why a Hedge Can Be Imperfect

By Daniel Sardá · Published on October 22, 2026

6 min read1,161 words

A hedge can offset much of a price move without removing it entirely. Basis risk explains that remaining difference.

A hedge seeks to reduce exposure to an adverse price movement. Yet the instrument chosen for the hedge does not always move in exactly the same way as the underlying good, asset, or price exposure. That difference creates basis risk: the possibility that the relationship between the exposure and its hedge will change unexpectedly.

This does not necessarily mean the hedge has failed. It may offset most of the movement while still leaving a residual gain or loss. Understanding that remainder helps assess a hedge by its net result, rather than by the mistaken expectation that it can erase all uncertainty.

The basis is not the same as basis risk

In a futures hedge, the basis is the difference between the spot price and the price of the related futures contract. This article uses the following convention:

Basis = spot price − futures price

If the spot price is 100 and the futures price is 98, the basis is 2. It is worth stating the convention because some sources calculate the difference in the opposite direction; the economic phenomenon is the same, but the sign changes.

The basis is an observable difference at a given point in time. Basis risk, by contrast, is the uncertainty about how that difference will change while the hedge remains open. The Commodity Futures Trading Commission (CFTC) distinguishes between the basis itself and the risk that it will unexpectedly widen or narrow.

Key idea: The basis is a measure; basis risk is uncertainty about how it will evolve.

When the exposure and the futures contract move by the same amount, the offset may come close to what was expected. If they move in different proportions, the hedge leaves a residual result. In that sense, hedging exchanges part of the risk of an absolute price for the relative risk between two prices.

Why the relationship between prices changes

The actual exposure and the hedging contract may look equivalent without being identical. Common sources of mismatch include:

• The asset or product: an exposure is hedged with a contract on a related, rather than identical, asset.
• Quality: different characteristics or grades can receive different prices.
• Location: transport, storage, and local conditions can affect the spot price without affecting the futures price to the same degree.
• Currency: the exposure and the contract may contain different foreign-exchange components.
• Quantity: a position that is too small leaves part of the exposure open; one that is too large can create an additional exposure.
• Maturity: the contract date may not match the date on which the exposure is bought, sold, or valued.

These factors reflect the fact that prices incorporate different information. A local price may respond to scarcity, logistics, or quality, while a broader futures contract incorporates conditions in another market. That dispersion of circumstances is connected to the dispersed information that the price system coordinates.

In some comparable deliverable contracts, spot and futures prices tend to converge as expiration approaches, as CME Group explains. But that tendency does not guarantee an exact hedge: many positions are closed before expiration, and others use contracts that are only substitutes for the actual exposure.

An example of incomplete offsetting

Suppose a buyer knows they will need to purchase a good later and is concerned that its price will rise. To limit that exposure, the buyer takes a futures position that gains value if the price rises.

At the start:

• spot price: 100;
• futures price: 98;
• basis: 100 − 98 = 2.

When the hedge is closed:

• spot price: 120;
• futures price: 116;
• basis: 120 − 116 = 4.

The cost of the good rose by 20, but the futures position gained 18. The futures gain offsets most, though not all, of the increase. The net cost is 102: the 120 paid in the spot market minus the 18 gained on futures.

The adverse residual is 2. It matches the strengthening of the basis, which moved from 2 to 4. The hedge was not useless: it avoided 18 of the 20 points of the increase. Nor was it perfect, because the relationship between the two prices changed.

Key idea: A hedge should be judged by how much it reduces net exposure, not by whether it produces a mathematically perfect offset.

The sign of the effect depends on the convention used, the direction of the hedge, and whether the basis strengthens or weakens. It is therefore safer to track the result of the exposure and that of the contract separately, then calculate the net result.

Correlation does not mean identity

High correlation indicates that two prices tend to move in the same direction or in a related way. It does not ensure that they change point for point or always maintain the same spread.

For example, an international futures contract and a local price may both rise. Even so, a logistical disruption or a change in quality may affect only the local price. Historical correlation can help guide the selection of a hedge, but it does not guarantee what the future basis will be.

Warning: Past co-movement does not remove mismatches in asset, place, quality, quantity, or timing.

Risks that should not be confused

Basis risk is specific to the relationship between an exposure and the instrument used to hedge it. It is not a synonym for other, related risks:

• Market risk is the possibility of losses from broad or specific price movements. A hedge seeks to reduce market exposure, but it can leave basis risk.
• Systematic risk refers to movements that affect the market broadly and are not eliminated through simple diversification. It does not describe the mismatch between the two components of a hedge.
• Foreign-exchange risk arises from changes in exchange rates. It may be the exposure a party wishes to hedge, while basis risk appears if the chosen hedge does not replicate that exposure well.

Nor does every residual difference, by itself, prove that an error was made. A reasonable objective may be to reduce a potentially large variation to a smaller, more manageable one. The problem arises when two prices are assumed to be interchangeable without examining their economic and contractual differences.

How it can be reduced, without promising it will disappear

Basis risk usually declines when the instrument more closely resembles the exposure in asset, quality, location, currency, quantity, and date. It also helps to define clearly which price is to be stabilized and to evaluate the hedge by the combined outcome.

Still, a close match does not turn futures into certainty. Contracts allow risks to be transferred and redistributed among participants willing to assume them on known terms; they do not eliminate incomplete information or changing circumstances.

The lesson is one of prudence: a hedge is a tool for limiting uncertainty, not a guarantee against it. Recognizing basis risk supports more realistic expectations, better comparisons among contractual alternatives, and continued responsibility for what the contract does not cover.