← Back to Blog · 2026-09-18 · 8 min read · Market Preview

You've probably seen this before: rebar spot quotes in Shanghai are holding firm, physical traders are complaining about tight inventory — and yet the futures contract is trading at a noticeable discount. Or the opposite: iron ore futures rip higher on sentiment while steel mills say the physical market is quiet. Your first instinct is to pick a direction and fade the move. Your second instinct, if you've been burned before, is to wonder whether there's a more structured way to trade this disconnect.

There is. It's called basis trading, and in Chinese commodity futures it's not an exotic strategy — it's the backbone of how the physical trade actually manages risk. For a retail trader coming from CME or EUREX products, understanding basis is probably the single fastest way to stop treating Chinese commodity futures like a casino and start treating them like a market with real gravity underneath the price.

This article breaks down what basis is, why it behaves differently in China than in Western markets, which contracts are worth watching, and how to build a practical framework around it.

What Basis Actually Is — And Why It Always Comes Home

Basis is simply the difference between the spot price of a commodity and the futures price of a related contract:

Basis = Spot price − Futures price

If rebar spot in a regional market is 3,700 RMB per ton and the most active futures contract trades at 3,620, basis is +80. If futures are above spot, basis is negative. Traders sometimes talk about the basis "strengthening" (futures getting weaker relative to spot) or "weakening" (futures catching up or overshooting).

Here's the part that matters: basis is anchored by delivery. A futures contract is a promise to deliver (or take delivery of) the physical commodity at expiry. As the contract approaches its delivery month, the spot and futures prices are pulled together by arbitrage. If futures trade far below spot, someone with access to the physical commodity can buy futures, deliver warehouse receipts, and pocket the difference — minus storage, financing, and delivery costs. If futures trade far above spot, industrial users can buy cheap physical and sell rich futures, or deliver against their short.

This convergence is not a theory; it's mechanical. The exact pace of convergence depends on carry costs (storage, insurance, funding) and on the deliverable grade specifications, but the direction is one-way: the gap dies at expiry.

What does that mean for you? Two things:

• Basis itself is tradable. You don't have to predict whether prices go up or down — you can trade whether the gap widens or narrows, which is often a more stable, supply-chain-driven relationship.
• Far-from-delivery contracts can detach violently. The further out the expiry, the more the futures price reflects expectations and sentiment rather than today's physical market. That's where both opportunity and danger live.

Why Basis Behaves Differently in China

If you've traded WTI or Brent, you know the spot-futures relationship there is heavily financialized — huge ETF flows, benchmark indices, and a spot market that's itself largely paper. Chinese commodity markets are different in three important ways.

1. The physical trade is genuinely dominant

Chinese commodity futures markets have some of the highest physical-industry participation rates in the world. Steel mills, ore traders, soybean crushers, and copper fabricators don't just watch these contracts — they hedge with them daily, and many deliver or take delivery. That means basis in Chinese commodity futures tends to be more responsive to real supply-chain conditions: warehouse inventories, mill margins, port stocks, seasonal construction demand.

2. Policy is a first-class variable

No serious China commodities trader ignores policy. The clearest recent example: the thermal coal rally in late 2021, when futures prices roughly doubled in a matter of months amid an energy crunch, before government intervention — supply increases, price guidance, and tightened speculative margin requirements — brought prices down sharply in a very short window. Futures overshot spot dramatically on the way up. Traders who understood that the futures premium had become unsustainable against a policy-constrained physical market had a map; traders who chased momentum had a lesson.

The 2020 oil crash taught a similar global lesson in a different form: when the spot-futures structure (contango) blew out to historic widths because storage was physically full, the basis/carry relationship itself became the trade. Same logic, different commodity.

3. Delivery mechanics are contract-specific

Each Chinese exchange has its own delivery rules, warehouse receipt system, and grade specifications. Rebar delivers against registered warehouse receipts in designated warehouses; iron ore has its own deliverable-brand and quality-premium system. If you're going to trade basis seriously, read the delivery specs on the exchange website (SHFE, DCE, ZCE, and the newer GFEX for industrial silicon and lithium carbonate). It's dry reading, but it tells you exactly what forces convergence.

The Contracts Worth Watching

Not every Chinese commodity futures contract is basis-friendly for an outside trader. These are the ones with deep liquidity, active physical hedging, and well-documented spot benchmarks:

A note on the numbers: contract multipliers and tick sizes above are the standard published specs, but exchanges do adjust margins, position limits, and sometimes trading parameters — always verify against the current exchange notice before sizing a position. Chinese contracts also settle in RMB, so your P&L in USD terms carries FX exposure on top of commodity exposure. Factor it in.

Three Practical Basis Frameworks

You don't need a physical warehouse to use basis logic. Here are three frameworks that work for a screen trader.

Framework 1: Convergence into delivery

The simplest one. When a contract is within roughly a month or two of delivery and basis is wide relative to the known carry costs, the gap tends to close. The trade: fade extreme spot-futures dislocations in the front month, with expiry as your catalyst. The risks: delivery-month liquidity thins out, exchanges raise margin sharply near delivery, and retail traders are often restricted from holding into the delivery window. Treat this as a signal and a timing tool, not a hold-to-expiry strategy.

Framework 2: Calendar-spread proxy for basis

If you can't observe or trade spot directly, the spread between the near and far contract is a readable proxy for the market's implied carry. When the far contract trades at a large premium to the near one (steep contango), the market is pricing tightness now and abundance later — or just speculation. When that spread moves sharply without any change in physical market conditions, that's often sentiment, not fundamentals, and mean-reversion in the spread becomes interesting. This is one of the cleaner ways to trade Chinese commodity futures without touching the physical market at all.

Framework 3: Basis as a directional filter

Even if you trade outright direction, basis should inform your bias. A simple rule set:

• Futures at a large discount to spot + falling warehouse/port inventories → the market is pricing fear the physical market doesn't support. Favor long setups; shorting into that basis structure is fighting gravity.
• Futures at a large premium to spot + rising inventories → speculative froth. Longs are fragile; a basis-driven pullback is the base case.
• Basis stable and consistent with carry costs → the market is functioning normally; trade your usual setups without a basis overlay.

This is exactly the kind of discipline that separated traders who navigated the 2021 coal episode from those who became part of its statistics.

Where the Traps Are

Basis trading is lower-drama than outright speculation, but it has its own failure modes:

• Carry cost miscalculation. Storage, funding, and delivery fees in China differ by commodity and by warehouse. If you estimate the "fair" basis wrong, you'll see dislocations that aren't there.
• Policy shocks. Margin hikes, trading limits, and export/import policy changes can blow through any basis model. In China this is not a tail risk; it's a recurring feature. Size accordingly.
• Delivery-grade basis. The futures price converges to the price of deliverable grades, not to whatever spot quote your data feed shows. Regional and quality premia mean your "spot" reference may not be the right anchor.
• Liquidity cliffs near delivery. The convergence trade looks great on a chart and terrible in the book when the front month's volume evaporates. Exit before the crowd does.

How to Actually Start

Here's a realistic first-month plan:

• Pick two contracts. Rebar and iron ore are the natural pair — related markets, deep liquidity, and a clear industrial logic between them (mill margins tie them together).
• Build a basis sheet. Daily, log the spot benchmark, the most-active futures price, the calculated basis, and key inventory data (rebar social inventories, iron ore port stocks — both are published weekly by Chinese consultancies).
• Define your thresholds before you trade. For example: only consider a convergence trade when basis exceeds some multiple of your estimated monthly carry, and only with X weeks to delivery. Write the numbers down before looking at charts.
• Backtest on real data, then forward-test. Chinese commodity futures data is available and the behavior is distinct enough from Western markets that assumptions imported from WTI or gold will mislead you.

That last step is where most traders cut corners, and it's the one that matters. If you want to pressure-test a basis-driven system against real Chinese market data — with proper risk limits, a defined evaluation period, and honest metrics — that's precisely what we built XS Select for. It's a China futures evaluation platform where you can run your framework on live-data conditions starting from $29, and trade the evaluation the same way you'd trade your own capital. No inflated promises from us — we're a new platform, and we'd rather you prove your edge on real data than read about someone else's.

The Bottom Line

Basis is the gravity of Chinese commodity futures. Sentiment can suspend it for weeks — the 2021 thermal coal squeeze proved that — but delivery mechanics and a physical trade that actually uses these markets always pull price back to earth. Learn to read the gap between spot and futures, respect the policy variable, anchor your analysis to the right deliverable-grade benchmarks, and you'll have a structural edge over the majority of outside traders who treat Chinese commodity futures as just another ticker.

The gap is the signal. Your job is to know why it exists, and when it has to close.