What is margin?

Margin is cash or assets provided under defined rules as collateral for borrowing or obligations in leveraged crypto trading or derivatives trading. It supports the account’s ability to bear risks from positions and liabilities. It is neither the full purchase price of the corresponding spot assets nor a trading fee.

On trading interfaces, “margin” can mean allocated collateral or a minimum amount that must be met. Margin balance, margin requirements and available balance are different concepts. Separating them is the first step toward understanding how funds are reserved, valued and released.

Why check margin when an account already holds assets?

In ordinary spot trading, traders exchange the relevant assets. Borrowing and margined contracts work differently: borrowing creates liabilities to repay, while contract positions can incur losses as prices change. The platform therefore continually assesses whether the account has sufficient collateral to bear these risks.

“How many assets the account holds” is not the same as “how much remains to support new trades.” Assets may already secure other positions or resting orders, or may be ineligible as collateral. Even eligible assets may count for less than their market value.

For example, an asset has a market value of $1,000. If hypothetical rules recognize only 90% as collateral, its recognized value is $900. This illustrates a collateral haircut, not any asset’s current parameter. It does not mean the platform has taken away $100 worth of assets.

What do margin, equity and available balance mean?

These fields answer different questions. Names and formulas depend on the account mode, but their functions should be distinguished:

Reserving margin is not charging a fee, and an unrealized loss is not always a cash deduction already made. Price changes may first affect unrealized results on open positions and eligible equity recognized under the rules. How closing or periodic settlement changes balances depends on the product’s settlement mechanism. Trading fees, settled funding fees and borrowing interest are separate flows.

Some platforms also display an estimated available balance. Actual order capacity can differ because of order price, collateral haircuts or reserved fees. A seemingly sufficient balance does not mean orders at any price and quantity will pass the checks.

How is collateral reserved and released during a trade?

Collateral serves different purposes from preparing an order to ending a position. This does not mean money is transferred away at every step.

When placing an order, a platform may reserve margin and fees for an unfilled opening order. The order can reduce available capacity before execution, preventing the same collateral from supporting several trades simultaneously. Freezing arrangements can differ between conditional order types.

After execution, the platform calculates collateral requirements from the actual position created. The initial allocation is not a permanently fixed risk boundary: changes in prices, fees, borrowing and collateral values can affect the account’s subsequent condition.

After cancellation or closing, unnecessary reservations are released under the rules. Closing usually also recognizes the relevant price result and calculates fees, so the amount released need not equal the initial reservation. If other positions or liabilities remain, not all remaining funds can necessarily be transferred out.

In borrowing-based trading, completing a purchase or sale does not necessarily repay the loan. Whether liabilities have been repaid and how interest settles require separate checks.

What stages do initial and maintenance margin govern?

Initial margin sets the collateral requirement for creating orders or positions; maintenance margin sets the minimum requirement while positions or liabilities remain.

For example, a linear contract calculates price results as underlying quantity multiplied by the price difference. Suppose its notional value is 10,000 USDT and its initial margin rate is a hypothetical 10%. Excluding other fees, the basic initial requirement is 1,000 USDT. USDT is the stablecoin asset’s ticker symbol, used here only as a denomination unit. Notional value is position size calculated from contract quantity and price, not funds already invested.

If the position is still worth 10,000 USDT at another time and the hypothetical maintenance margin rate is 0.5%, the basic maintenance requirement is 50 USDT. These figures show that opening and maintaining a position have different thresholds. They do not establish that the position can necessarily lose 950 USDT: actual risk checks also consider changing values, tiers and fees.

When eligible equity is insufficient, a platform may cancel orders that reserve capacity, reduce positions or liquidate them. It does not guarantee an advance margin call that can be acted on in time. See liquidation for the process.

Isolated and cross margin differ in which assets provide collateral

Isolated margin usually allocates margin separately to a particular position and assesses its risk separately. Other funds do not automatically secure that position merely because they are held on the same platform. Features such as automatic margin additions may change the allocation scope.

Cross margin allows eligible funds within the same risk-calculation scope to support positions jointly. One position’s losses affect shared equity; other positions or collateral assets can in turn affect it. “Cross” does not mean all assets owned by the user unconditionally provide collateral.

The core difference is the scope of risk calculations and shared funds, not that either mode necessarily protects other funds from losses or is necessarily harder to liquidate. Assessment also depends on automatic additions, fees, asset eligibility and negative-balance rules.

Why distinguish collateral assets from settlement assets?

Collateral assets secure obligations; settlement assets record or pay gains and losses. They need not be identical. Some unified accounts, for example, recognize eligible assets such as BTC at adjusted values as collateral for USDT-settled contracts. Contract results in USDT and collateral value in BTC can both change.

Thus, even if a position’s price result is temporarily unchanged, depreciation of its collateral assets can reduce its collateral capacity. Conversely, holding a settlement asset does not mean every account mode accepts it fully and unconditionally as collateral.

Margin is not an independent source of returns. It is an arrangement linking assets, liabilities, positions and risk requirements. An accurate account explanation asks: which assets provide collateral, what value is recognized, which risks reserve that value, and when it can be released.

Related terms

Explore initial margin, maintenance margin, margin ratio and leverage, or return to the crypto glossary.

References

• OKX: Futures margin calculation rules
• OKX: Borrowing interest in margin trading
• OKX: Liquidation FAQ