← Back to Blog · 2026-10-24 · 6 min read · Market Preview

If you have ever stared at a chart of Shanghai Rebar (RB) or Iron Ore (I) futures, wondering why the price stayed flat even though news headlines screamed about a massive construction stimulus, you have encountered the silent killer of retail traders: the basis.

In the US or European markets, supply and demand often react in near real-time. But in China, the distance between the paper price (futures) and the physical reality (spot) is dictated by a specific, heavily monitored metric: social inventory and warehouse stocks. These are not just numbers in a weekly report; they are the pulse of the physical market. For global retail traders looking to diversify into Chinese commodity futures, ignoring these stocks is like driving a car with the fuel gauge taped over. You might move, but you won’t know if you’re running on fumes.

This guide breaks down how to read warehouse stocks, why they matter for the basis trade, and how to use this logic to execute high-probability setups in the Chinese futures market.

The Anatomy of the Chinese Futures Contract

Before we dive into inventory, we must understand the vehicle. Trading Chinese commodities is not identical to trading WTI Crude or Gold. The contract specifications are rigid, and the leverage is high. If you are treating these like standard CFDs, you will get stopped out by volatility alone.

Let’s look at the two most popular contracts for global traders: Rebar (RB) and Iron Ore (I), both traded on the Shanghai Futures Exchange (SHFE) and Dalian Commodity Exchange (DCE) respectively.

Practical Note: The Iron Ore contract is massive. A single tick move is 50 CNY. With leverage, a small adverse move can wipe out a small account quickly. Always check your broker’s specific margin requirements, as they often add a buffer above the exchange minimums. For Rebar, the 10 CNY tick is manageable, but liquidity can dry up during lunch hours in China (11:30–13:30 CST), leading to slippage. Plan your entries around the opening (09:00 CST) or the afternoon session start (13:30 CST).

Defining the Basis: The Gap Between Paper and Physical

The basis is simply the difference between the spot price of the physical commodity and the futures price. In Chinese markets, this relationship is not static; it is cyclical and driven by inventory levels.

Basis = Spot Price – Futures Price

When the basis is negative (Futures > Spot), it is called a contango or "normal" market structure in many Western contexts, but in China, it often signals that traders expect future supply to be tight or demand to surge. When the basis is positive (Spot > Futures), it is backwardation, indicating immediate physical scarcity.

Why does this matter? Because the futures contract must converge with the spot price at expiration. If you understand where the inventory is, you know which way the basis will move. This is the core of the basis trade.

Reading the Inventory Data: The Weekly Ritual

China’s market is data-heavy. Every Thursday (for steel products) and Wednesday (for iron ore), major agencies like Mysteel and Shagang release inventory data. These reports are the "earnings calls" of the commodity world.

1. Social Inventory vs. Producer Inventory

Do not lump all stocks together. You must distinguish between:

• Social Inventory: Steel sitting in warehouses, trading centers, and downstream dealers. High social inventory means supply is abundant and easy to buy. This usually pressures the spot price down, widening the negative basis or pushing futures lower.
• Producer Inventory: Steel sitting at the mill (e.g., Baosteel, HBIS). High producer inventory forces mills to cut production or offer discounts to clear stock. This is bearish for the futures curve.

Actionable Rule: If Social Inventory is rising week-over-week while futures prices are rising, the rally is likely a "short squeeze" or speculative positioning, not fundamental strength. This is a prime area to look for a mean-reversion short, provided the basis is already deeply negative.

2. The Seasonal Cycle

Chinese construction is highly seasonal. The "Golden March" and "Silver April" are traditional peak demand periods for steel. Conversely, the rainy season (June–August) and winter holidays (Jan–Feb) slow down construction.

During the off-season, inventory builds up. If you see inventory peaking in April when it should be drawing down, it indicates weak demand. This divergence between inventory trends and price trends is your signal. For example, in 2021, the thermal coal rally was driven by genuine supply shortages. In contrast, certain rebar rallies have failed because inventory was building despite price hikes, signaling a disconnect that eventually corrected violently.

Executing the Basis Trade: Two Practical Strategies

Now, let’s move from theory to execution. Here are two ways to trade this data.

Strategy 1: The Inventory Divergence Short

This strategy works best when futures prices are rallying on news (e.g., infrastructure stimulus rumors) but physical data contradicts it.

• Setup: Rebar futures are up 3% on the week. News is bullish.
• Check Data: Look at the latest Mysteel report. Is Social Inventory rising? Are mill margins compressing?
• Trigger: If inventory is rising while price rises, the basis is becoming excessively negative (Futures >> Spot).
• Execution: Enter a short position on the front-month contract. Set a stop-loss above the recent swing high. The logic is that the physical market will eventually force the futures price down to match the abundant supply.

Strategy 2: The Backwardation Long

This is a momentum strategy driven by physical scarcity.

• Setup: Iron Ore prices are consolidating or dipping.
• Check Data: Port inventories (for Iron Ore) are at multi-year lows. Shipping delays are reported.
• Trigger: The spot price spikes above the futures price (Positive Basis/Backwardation).
• Execution: Buy the futures contract. The expectation is that the futures price will rise to meet the higher spot price as arbitrageurs rush to buy physical material, or simply because the market recognizes the tight supply.

Risk Management: Basis trades can take time to converge. Unlike scalping, you are betting on a fundamental shift. Use wider stops and position sizes no larger than 1-2% of your account equity per trade. In Chinese futures, daily limit moves (typically 4-8% depending on the contract) can gap you out, so hedging or strict stop-losses are non-negotiable.

Common Pitfalls for Global Traders

Many traders coming from the US or Europe make three critical errors when trading Chinese commodities:

1. Ignoring the Policy Hand: China’s government actively intervenes to stabilize prices. If rebar prices rise too fast, state media will issue warnings, and exchanges may raise margins. Always monitor official news feeds (Xinhua, People’s Daily) for regulatory tone changes.
2. Overlooking Currency Risk: You are trading CNY-denominated assets. If you are funded in USD or EUR, currency fluctuations can impact your P&L, though most platforms handle this via conversion spreads. Be aware of the RMB/USD exchange rate trend.
3. Trading the Wrong Contract Month: Liquidity is concentrated in the 1st, 5th, and 10th months (e.g., RB2401, RB2405, RB2410). Do not trade illiquid months. The spread between these months also tells you about inventory expectations. A steep backwardation in the curve signals immediate tightness.

Testing Your Edge Before You Commit

Understanding warehouse stocks is one thing; executing a profitable strategy around that data is another. The Chinese futures market is fast, data-driven, and unforgiving. Before risking real capital, you need to prove that your interpretation of inventory data translates into consistent P&L.

This is where discipline meets opportunity. Many traders fail not because they lack insight, but because they lack a structured environment to test their hypotheses under real market conditions without the emotional weight of immediate capital loss. If you have developed a system based on inventory divergence or basis convergence, you need to validate it against live data.

At XS Select, we provide the world’s first specialized evaluation platform for China futures traders. You can test your basis trading system against real-time market data, adhering to strict risk management rules that mimic professional prop firm standards. It’s not about guessing; it’s about proving your edge. You can start your evaluation from $29, giving you a low-cost way to verify if your understanding of Chinese commodity futures holds up under pressure.

Remember, in the Chinese market, the data is public, but the edge lies in how quickly and accurately you can interpret the relationship between the warehouse and the ticker. Master the basis, respect the inventory, and manage your risk. The market will reveal its direction to those who are prepared to listen.