Margin Is Collateral, Not Purchase Price

A futures position creates exposure to a contract’s full notional value while requiring only a fraction of that value as collateral. Notional value equals futures price multiplied by the contract multiplier. If a crude oil futures contract represents 1,000 barrels and trades at $75.00 per barrel, its notional value is $75,000.

Initial margin is the collateral required to open a position. Assume the exchange or broker requires $7,500. The trader controls $75,000 of exposure with $7,500, implying 10:1 notional leverage because $75,000 divided by $7,500 equals 10. A 1% move in the contract’s notional value therefore produces approximately a 10% change relative to the initial margin, before fees and any margin adjustments.

Maintenance margin is the minimum account equity that must be maintained after entry. If maintenance margin is $6,000, opening the position with $7,500 does not mean the trader can lose the entire $7,500 without intervention. Once equity falls below $6,000, the broker may issue a margin call, restrict trading, or liquidate the position according to its agreement and risk controls. Initial and maintenance requirements can also increase when volatility rises, even if the futures price is unchanged.

Daily Mark-to-Market and Variation Margin

Futures are marked to market, usually at least once each trading day using the exchange’s settlement price. Gains are credited and losses are debited in cash. Variation margin is the cash transferred because of this settlement process; it is not a separate permanent deposit like initial margin.

Consider one long crude oil contract with a 1,000-barrel multiplier. The entry price is $75.00, initial margin is $7,500, maintenance margin is $6,000, and starting account equity is $7,500. If the Day 1 settlement price is $74.40, the daily price change is $74.40 minus $75.00, or negative $0.60 per barrel. Daily profit and loss is negative $0.60 multiplied by 1,000, or negative $600. Ending equity is $7,500 minus $600, or $6,900. Equity remains above maintenance margin.

If Day 2 settles at $73.70, the daily change is $73.70 minus $74.40, or negative $0.70. The variation loss is $700, so equity becomes $6,200. The cumulative loss since entry is $1,300, which also equals the $1.30 price decline multiplied by 1,000.

If Day 3 settles at $73.40, the daily loss is $300 and equity falls to $5,900. Equity is now $100 below the $6,000 maintenance requirement. If the broker requires restoration to the $7,500 initial-margin level, the margin call is $7,500 minus $5,900, or $1,600. Depositing only $100 would reach maintenance but would not satisfy a call requiring restoration to initial margin.

Liquidation Thresholds and Gap Risk

A simplified estimate of the adverse price move that consumes the margin buffer is: margin buffer divided by contract multiplier. Here, the buffer between initial and maintenance margin is $7,500 minus $6,000, or $1,500. Dividing $1,500 by 1,000 barrels gives $1.50 per barrel. From a $75.00 entry, a decline toward $73.50 would reduce equity to approximately maintenance margin, assuming no fees, no prior gains or losses, and unchanged margin requirements.

This estimate is not a guaranteed liquidation price. Brokers may apply intraday risk checks, liquidation fees, house-margin requirements, position limits, or additional buffers. Markets can also gap through the estimated threshold. If price drops directly from $75.00 to $70.00, the loss is $5.00 multiplied by 1,000, or $5,000. Equity falls from $7,500 to $2,500, far below maintenance. If execution during forced liquidation occurs at $67.00 instead, the $8,000 loss exceeds the original $7,500 deposit by $500 before fees. Futures losses can therefore exceed the cash initially posted.

Short positions face the same mechanism in the opposite direction. A short loses when settlement prices rise. What matters is adverse price movement multiplied by the contract multiplier, not whether the position is long or short.

Position Sizing and Risk Controls

Margin capacity and loss tolerance are different constraints. A trader with $30,000 might technically open four contracts if initial margin is $7,500 each, but that would use all available equity and leave no excess liquidity. A $0.60 adverse move across four crude oil contracts would create a $2,400 loss, equal to 8% of the account.

Suppose the trader limits planned trade risk to 2% of $30,000, or $600. With a stop distance of $0.50 per barrel, risk per contract is $0.50 multiplied by 1,000, or $500 before slippage and fees. The risk budget permits one contract, even though margin capacity permits four. The trader should also keep cash available for variation margin and possible increases in exchange or broker requirements.

A protective stop can reduce ordinary market risk but cannot guarantee the exit price during a gap or illiquid period. Practical control requires monitoring account equity, excess margin, settlement exposure, contract multipliers, volatility, and broker liquidation rules. The central lesson is that leverage accelerates the transfer of gains and losses, while mark-to-market converts those changes into immediate cash demands.