The exchange most gold headlines quote isn’t where the metal changes hands, it’s where the price gets argued out.

Key takeaways

• COMEX is the New York metals arm of CME Group and the largest venue for trading gold futures, contracts to buy or sell gold at a set price on a future date.
• The standard COMEX gold contract covers 100 troy ounces; smaller 50-ounce and 10-ounce versions let more traders in.
• COMEX does not set the physical “spot” benchmark on its own, the LBMA Gold Price is fixed in London, and the two markets track each other through arbitrage.
• Futures are leveraged and margined, so losses can move faster and run larger than the cash you put up.

When a news story says gold “hit a record” or “fell on the day”, the number it quotes almost always comes from COMEX. That single fact explains why this exchange matters far more than its physical footprint suggests. Very little actual metal moves through it. What moves through it is opinion, thousands of institutions, funds and dealers taking positions on where the gold price is heading, and in doing so, helping decide what that price is.

COMEX gold sits at the centre of the gold derivatives market, but it is one of two pillars, not the whole structure. The other is London’s over-the-counter market, where the physical benchmark is set. Understanding how the CME gold futures market works, how it connects to London, and where its influence stops is the difference between reading the gold price correctly and misreading it.

What COMEX gold is and where it sits inside CME Group

COMEX stands for Commodity Exchange, founded in New York in 1933 out of a merger of four smaller commodity exchanges. It ran independently, merged into the New York Mercantile Exchange (NYMEX) in 1994, and became part of Chicago-based CME Group in 2008, when CME Group completed its acquisition of NYMEX Holdings and folded its energy and metals business in.

The corporate map is worth getting right, because the names get used loosely. CME Group is the parent, headquartered in Chicago. COMEX is its New York metals division, the part of the old NYMEX that lists gold, silver, copper and other metals. So when a trader talks about “COMEX gold” or “CME gold futures”, they are describing the same market: gold futures listed on CME Group’s metals exchange.

A gold futures exchange is not a place where you buy bars. It is a marketplace for standardised contracts, legally binding agreements to buy or sell a fixed quantity of gold at an agreed price on an agreed future date. That standardisation is the point. Because every contract is identical, they trade almost like a currency, which is what gives COMEX its liquidity.

How COMEX gold contracts work

The headline instrument is the standard gold futures contract, ticker GC. Each one covers 100 troy ounces of gold, quoted in US dollars per ounce, and any metal delivered against it must assay to a minimum fineness of 995, per the COMEX gold contract specifications. At a gold price around US$3,000 an ounce, one contract controls roughly US$300,000 of metal, too large for most individuals to use directly.

That is why CME Group lists smaller versions. The E-mini gold contract (QO) covers 50 troy ounces, and the Micro Gold contract (MGC) covers just 10 ounces, one-tenth of the standard, as set out in the Micro Gold contract specifications. Micro Gold volume has surged with the gold price, and the smaller unit size is a large part of why: it lets a wider pool of traders take a position without committing six figures per contract.

You do not pay the full contract value to trade one. You post margin, a good-faith deposit, often a low single-digit percentage of the notional value, and the exchange marks your position to market each day. This is leverage. A 2% margin means a 2% move in gold roughly doubles or wipes out your deposit. The mechanism that lets a small account trade a large quantity of gold is the same mechanism that turns a modest price move into an outsized gain or loss.

Most COMEX gold positions never end in delivery. Traders close out before expiry, settling the cash difference. But the option to take physical delivery is real and it matters: contract holders who stand for delivery receive warrants against gold held in CME-approved depositories, and the metal is graded as “registered” (available for delivery) or “eligible” (stored but not currently offered), per Chapter 113 of the COMEX rulebook. That deliverable link is what keeps the futures price tethered to real metal rather than floating free of it.

Contango, backwardation and the cost of carry

A future almost never trades at the same price as gold for immediate delivery. The gap has a name, the basis, and a cause: the cost of carry, meaning what it costs to hold physical gold until the delivery date. That cost is mostly financing (the interest on the money tied up in the metal) plus storage and insurance.

When futures trade above the spot price, the market is in contango, which is gold’s normal state because carrying costs are positive. When futures trade below spot, it is in backwardation, usually a sign of tight physical supply or strong immediate demand.

A worked example makes it concrete. Take spot gold at US$3,000 an ounce (illustrative, not a live quote). At a 5% annual financing rate, carrying an ounce for three months costs about US$37.50, plus a little for storage and insurance. So a three-month future should trade near US$3,040, roughly a 1.3% premium to spot. That premium is the basis, and it should decay to zero as the contract approaches expiry, because on delivery day the future and the physical metal are the same thing. Arbitrage desks earn a living forcing that relationship to hold.

How COMEX and London together set the gold price

Here is the part that gets stated wrongly most often. COMEX does not, on its own, “determine the spot price used by dealers across the world.” The physical spot benchmark is set in London.

The LBMA Gold Price is fixed twice a day, at 10:30 and 15:00 London time, through an electronic auction run by ICE Benchmark Administration. Direct participants enter buy and sell orders round by round until the imbalance falls within a set tolerance, and the clearing price becomes the benchmark. This is the number that settles physical contracts, prices most gold ETFs, and anchors dealer premiums worldwide.

So the two markets do different jobs. London is where physical gold clears and the benchmark is struck; COMEX is where the largest pool of futures liquidity sits and where much of the minute-to-minute price movement originates. In 2025, COMEX gold futures averaged about US$114bn of trading a day and the London OTC market about US$160bn, out of roughly US$361bn traded globally, according to the World Gold Council. On those figures the two venues together handle close to three-quarters of daily gold turnover, the dual pillars of price discovery. Older academic work on where the gold price is set puts London and New York’s combined share higher still, in the 80-90% range; treat the exact figure as indicative, because it moves with market conditions and how turnover is measured.

The point stands either way: gold has no single price-setting venue. It has two dominant ones, wired together by arbitrage, so a move on COMEX shows up in London spot within seconds and vice versa.

Turnover figures as at 2025 per the World Gold Council; refresh annually.

The London and UK angle

London’s weight in this system is physical, not electronic. The city is the settlement hub for the global bullion market, and the vaults beneath it, commercial vaults plus the Bank of England, held about 9,392 tonnes of gold at the end of May 2026, worth roughly US$1.4 trillion, per LBMA London vault data. (As at May 2026; the LBMA updates this monthly, so treat the figure as a snapshot needing refresh.)

For anyone buying or pricing gold from the UK, two practical points follow. First, the LBMA Gold Price is published in US dollars (and in sterling and euro), but the reference rate the world watches is the dollar one, so a UK holder carries currency risk between the dollar gold price and the pound. Second, the link between London metal and New York futures occasionally strains: when the COMEX price runs far enough above London spot, traders ship physical gold across the Atlantic to deliver against contracts, a “loco-London” arbitrage that normally keeps the two prices in line but can widen sharply in stressed markets.

The risk that leverage hides

Gold futures are complex, leveraged instruments, and the leverage cuts both ways. The Financial Conduct Authority warns that leveraged derivatives are high-risk products where trading on margin multiplies both profits and losses, and losses can exceed the money originally deposited. The FCA’s rules target contracts for difference sold to retail clients, but the underlying mechanic, margin turning a small price move into a large account move, is exactly the same on an exchange-traded gold future.

That is the trade-off at the heart of COMEX. The same efficiency that makes it the world’s deepest gold futures market, small deposits controlling large quantities of metal, is what makes it unforgiving to anyone who treats a 100-ounce contract like a savings account. This is general information, not financial advice.

FAQs

Is COMEX the same as the CME?

COMEX is the metals division of CME Group. CME Group is the Chicago-headquartered parent; COMEX is its New York exchange for gold, silver and other metals. “COMEX gold” and “CME gold futures” refer to the same contracts.

Does COMEX set the gold price?

Not on its own. The physical benchmark, the LBMA Gold Price, is set in London through a twice-daily auction. COMEX is the dominant futures venue and drives much of the short-term price movement, but the two markets set the price together, kept in line by arbitrage.

Can you actually get gold from a COMEX contract?

Yes. Most positions are closed for cash before expiry, but a holder can stand for delivery and receive warrants against gold in CME-approved depositories. The metal must meet a minimum 995 fineness.

Why are there mini and micro gold contracts?

The standard contract’s 100 ounces is worth hundreds of thousands of dollars, too large for most individual traders. The 50-ounce E-mini and 10-ounce Micro Gold contracts give smaller accounts a way to take a position in the same market.

What is the basis in gold futures?

The basis is the gap between the futures price and the spot price. It reflects the cost of carrying physical gold, mainly financing plus storage, and it shrinks to zero as a contract nears delivery.

Next read

For the other main route into gold and commodities, the listed products most investors actually use, see Exchange-Traded Commodities explained: how ETCs work and how they compare with ETFs, part of our commodities investing guide.