Commodity ETF Contango and Backwardation: How Rolling Costs Affect Returns

What Is Contango?

Contango describes a futures market where contracts for later delivery are priced higher than contracts for near-term delivery. This is the normal state for most commodity markets because of storage costs, insurance, financing costs, and the time value of money. For example, if crude oil is trading at $70/barrel for immediate delivery (spot price), the one-month futures contract might be $71, the two-month contract might be $72, and so on. The upward-sloping curve reflects the cost of storing and financing the oil for delivery in the future.

For a commodity ETF that rolls contracts monthly, contango creates a persistent cost. The ETF holds the near-month contract and must sell it before expiration. It sells at the near-month price and buys the next-month contract at a higher price. Each roll loses the difference between the two contract prices. Over many months and years, these small losses compound into significant underperformance relative to the spot commodity price. USO (United States Oil Fund) is the textbook example: from 2009 to 2019, crude oil spot prices were approximately flat (around $50-$60/barrel at both ends), but USO lost approximately 70% of its value due to persistent contango in the oil futures market. The ETF tracked the futures returns, not the spot returns, and the futures market consistently priced in a positive cost of carry. Crude oil investing deep dive →

What Is Backwardation?

Backwardation is the opposite of contango: futures contracts for later delivery are cheaper than the spot price or near-month contract. This occurs when there is immediate demand pressure for the commodity — buyers are willing to pay a premium for prompt delivery because supply is tight. Backwardation is more common in commodities with high storage costs or supply disruptions, such as crude oil during supply crises, agricultural commodities after crop failures, or natural gas during cold winters.

For commodity ETFs, backwardation creates a positive roll yield. The ETF sells its near-month contract at a higher price and buys a cheaper next-month contract, capturing the difference as profit. During periods of backwardation, a commodity ETF can generate positive returns even if the spot price stays flat. For example, during the 2022 energy crisis, crude oil futures were in backwardation, and USO generated positive roll yield. The same dynamics apply to other commodity ETFs like UNG (natural gas) and DBA (agriculture), though these markets experience contango and backwardation at different times depending on supply and demand conditions. The key insight is that commodity ETF returns depend on both the direction of commodity prices and the shape of the futures curve. Natural gas investing and futures curves →

How to Measure and Predict the Futures Curve

The shape of the futures curve is measured by comparing futures prices at different maturities. The simplest metric is the spread between the near-month and next-month futures contract. A positive spread (next-month higher than near-month) indicates contango. A negative spread (next-month lower than near-month) indicates backwardation. The steepness of the curve matters: a steep contango implies larger roll costs, while steep backwardation implies larger roll benefits.

The futures curve is driven by the cost of carry: storage costs, financing costs, and the convenience yield. Convenience yield is the benefit of holding the physical commodity rather than a futures contract. When inventories are high, convenience yield is low and contango tends to prevail. When inventories are low, convenience yield is high and backwardation is more likely. This inverse relationship between inventory levels and the futures curve means that commodity ETF investors should pay attention to storage data, such as the EIA's weekly crude oil inventory report and the DOE's natural gas storage report. Commodity markets with high storage costs (natural gas, crude oil) are more prone to contango, while markets with low storage costs (gold, silver) tend to have flatter futures curves with less roll impact.

Some commodity ETFs attempt to mitigate roll costs by using optimized roll strategies. These funds do not simply roll from near-month to next-month. Instead, they may hold a portfolio of futures contracts across multiple maturities to reduce the impact of contango. The United States Commodity Index Fund (USCI) and the iShares S&P GSCI Commodity-Indexed Trust (GSG) use different roll methodologies. However, no strategy can fully eliminate roll costs in contango markets — the cost is inherent in the futures market structure. Investors should understand the specific roll methodology of any commodity ETF they own and monitor the futures curve for changes. Compare ETF costs and strategies →

Commodity-Specific Roll Cost Analysis

Crude oil (USO): Contango has been the dominant state for most of the past 15 years, except during supply crises. USO's long-term track record shows significant negative roll yield, making it unsuitable for long-term holding. Oil ETFs are best used for short-term tactical trades rather than strategic buy-and-hold positions.

Natural gas (UNG): Natural gas has the steepest contango of any major commodity due to very high storage costs (requires cryogenic cooling). UNG has even worse roll costs than USO. Natural gas ETFs are extremely volatile and suffer severe negative roll yield over time. They are only suitable for very short-term trades.

Gold (GLD, IAU): Gold ETFs that hold physical bullion have zero roll cost — they do not use futures contracts. This is a major advantage. Gold is unique among commodities in having widely available physically-backed ETFs. Gold futures ETFs do exist but are much less common.

Agriculture (DBA, CORN, WEAT): Agricultural commodities experience both contango and backwardation, depending on growing seasons, weather, and harvest cycles. Roll costs are generally lower than for energy commodities, but agricultural ETFs are still subject to futures curve dynamics. The seasonal nature of agriculture means that roll costs can be somewhat predictable based on the time of year.

Broad commodities (DBC, GSG): Broad commodity indices hold a diversified basket of futures contracts, so the roll yield is an average of the contango/backwardation across all included commodities. This diversification reduces the impact of any single commodity's roll cost but does not eliminate it. Broad commodity ETFs have historically experienced slight negative roll yield on average, but with significant variation over time. Oil and gas investing guide →

What is contango in commodity ETFs?

Contango is when futures contracts for later delivery are more expensive than near-month contracts. For commodity ETFs that roll contracts monthly, this creates a persistent cost — they sell near-month contracts at lower prices and buy next-month contracts at higher prices. Over time, these roll costs can significantly erode returns. USO (crude oil ETF) lost 70% from 2009-2019 due to contango, while crude oil spot prices were flat. Contango is the normal state for most commodity markets due to storage costs and financing costs.

How does backwardation affect commodity ETFs?

Backwardation is the opposite of contango — later-month futures are cheaper than near-month contracts. In backwardation, commodity ETFs generate a positive roll yield because they sell near-month contracts at higher prices and buy cheaper next-month contracts. Backwardation occurs when there is immediate supply pressure, such as during oil supply crises or agricultural supply disruptions. During backwardation, an ETF can generate returns even if the spot price stays flat. Backwardation is less common than contango but can significantly boost commodity ETF returns when it occurs.

Which commodity ETFs have the lowest roll costs?

Physically-backed commodity ETFs have zero roll costs because they hold the physical commodity instead of futures contracts. Gold ETFs (GLD, IAU) and silver ETFs (SLV) are the main physically-backed options. For commodities that do not have physically-backed ETFs, the lowest roll costs occur in markets that are frequently in backwardation. Broad commodity ETFs (DBC, GSG) diversify across multiple commodities, reducing the impact of any single commodity's roll cost. Some commodity ETFs use optimized roll strategies (like USCI) that hold multiple maturities to mitigate contango. However, no futures-based ETF can completely eliminate roll costs in contango markets.

Can I avoid contango costs when investing in commodities?

Yes, several strategies can avoid or reduce contango costs. Invest in physically-backed commodity ETFs (gold, silver) that hold the physical asset. Use commodity equity ETFs (like XLE for energy stocks) instead of futures-based ETFs — these hold company stocks, not futures, so there is no roll cost. Invest in structured notes or commodity-linked notes (but these carry issuer credit risk). Use a commodity futures managed account or actively managed commodity fund that can adjust positions based on the futures curve. Or simply accept roll costs as a cost of commodity investing and limit your allocation to a small percentage of your portfolio. For long-term commodity exposure, physically-backed gold and silver ETFs are the most cost-effective options because they avoid roll costs entirely.

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