Isolated margin vs cross margin describes two ways collateral supports crypto futures: isolated margin assigns collateral separately to a position, while cross margin lets eligible collateral in the applicable shared pool support cross positions. The choice changes loss allocation and capital exposure, not the trading PNL of an otherwise identical position.
This article focuses on margin modes for crypto futures. It does not cover spot margin borrowing or portfolio-margin systems.
Key Takeaways
- Isolated margin separates the collateral assigned to one position from collateral outside that position.
- Cross margin shares eligible collateral within a pool, potentially providing a larger buffer while exposing more collateral.
- Margin mode controls collateral allocation; leverage controls the initial margin required for a given position size. They are related settings, not the same setting.
- Identical positions experience identical trading PNL from the same price move, regardless of margin mode.
- Neither mode prevents liquidation. Fees, funding, other positions and changes in account equity can all affect the remaining buffer.
What Is Isolated Margin?
In isolated margin mode, collateral is assigned to a position. Its margin, unrealised PNL, maintenance requirement and liquidation risk are assessed separately from other isolated positions. A loss reduces supporting equity; liquidation can occur once maintenance and fee requirements are not met.
Collateral outside the position is not automatically drawn in unless the trader adds margin or an enabled automatic-margin feature does so. Therefore, isolated mode makes position-level exposure easier to monitor, but it does not guarantee that losses are limited to the original deposit: additions, funding, fees and platform rules can increase the capital connected to the position.
What Is Cross Margin?
In cross margin mode, eligible collateral in a defined pool supports cross-margin positions together. A loss on one position reduces shared equity and can affect other positions’ buffers. Profits elsewhere may offset losses only where account rules permit them to count.
“Shared” does not mean every exchange asset is at risk. Scope depends on the futures account, settlement asset, collateral eligibility and account asset mode. MEXC’s web futures guide says Single-Asset Margin shares collateral among positions with the same settlement asset; Multi-Asset Margin can use multiple supported assets and supports cross only.
Cross margin can give one position a larger buffer, but continued losses may consume collateral not initially required to open it and worsen risk elsewhere in the pool. It does not prevent liquidation.
Isolated Margin vs Cross Margin at a Glance
| Feature | Isolated margin | Cross margin |
|---|---|---|
| Collateral allocation | Assigned separately to a position | Eligible collateral is shared within the applicable margin pool |
| Interaction between positions | Other isolated positions are generally assessed separately | Losses and permitted gains from other cross positions can change shared equity |
| Liquidation considerations | Mainly position margin, PNL and requirements | Shared equity, relevant positions, orders and requirements |
| Margin monitoring | Position margin, liquidation price and risk indicator | Pool equity, risk and every shared position |
| Additional funds at risk | Normally limited to allocated and later-added collateral, subject to fees and platform rules | More eligible collateral in the pool may support a losing position |
| Effect on trading PNL | No change for the same position size and price move | No change for the same position size and price move |
Conceptual Comparison: The Same BTC Position in Each Mode
This conceptual illustration compares two hypothetical linear, USDT-margined BTC perpetual setups; it is not every MEXC account’s mechanics. Maintenance margin, liquidation fees, trading fees and funding are ignored, so no liquidation price is calculated.
In both scenarios:
- Starting collateral: 1,000 USDT
- Entry price: 50,000 USDT per BTC
- Position size: 0.04 BTC
- Initial position notional: 50,000 × 0.04 = 2,000 USDT
- Selected leverage: 10×
- Initial margin requirement: 2,000 ÷ 10 = 200 USDT
- No other positions or orders
If BTC declines to 47,500 USDT, the unrealised trading loss is:
(47,500 − 50,000) × 0.04 = −100 USDT
Scenario A: Isolated Margin
The trader assigns 200 USDT to the position and leaves 800 USDT outside it. Automatic margin addition is disabled, and no margin is added manually. After the loss, the position’s simplified margin equity falls from 200 to 100 USDT; the other 800 USDT stays outside its collateral. Continued losses may lead to liquidation without automatically drawing in that 800 USDT under these assumptions.
Scenario B: Cross Margin
Assume all 1,000 USDT is eligible collateral in the same cross-margin pool. After the loss, simplified shared equity falls from 1,000 to 900 USDT. Continued losses may draw on the wider pool, giving the position more room while exposing more collateral.
The loss is identical because position size and price move are identical. The 100 and 900 USDT figures are simplified equity—not available margin, transferable funds or withdrawable balances.
Margin Mode and Leverage Are Different Choices
Selected leverage determines the initial margin for a given notional position: at 10×, the example’s 2,000 USDT position requires 200 USDT before fees. Margin mode instead determines which collateral can support it.
Selected leverage remains 10× in both. Yet notional divided by isolated collateral is 2,000 ÷ 200 = 10, versus 2,000 ÷ 1,000 = 2 for the assumed cross pool. This conceptual exposure comparison is not necessarily a platform’s effective-leverage metric. Changing mode does not change position size, entry or PNL.
Manual and Automatic Margin Addition
Adding margin to an isolated position increases supporting equity and ordinarily improves its liquidation buffer, all else equal. It also increases the capital exposed.
MEXC’s Auto Margin Addition guide says it is isolated-only. It transfers available futures-wallet funds as liquidation approaches and may first cancel opening orders. Repeated additions can consume the balance; liquidation may still occur.
Cross margin already relies on its shared pool, so it does not use that separate auto-add function. Orders, funding, fees, transfers and losses elsewhere can still reduce shared equity.
How Multiple Cross Positions Affect One Another
If a BTC long and ETH short share a pool, a BTC loss reduces shared equity and may bring the ETH position closer to liquidation. An ETH gain may offset part of it only if account rules allow; unrealised profit should not be assumed transferable or withdrawable.
Cross-margin liquidation does not simply mean every position closes at once. MEXC’s liquidation FAQ describes order cancellation, cross-mode long-short reduction, partial liquidation at higher risk tiers and full takeover only if risk remains excessive at the lowest tier. Fair price—not merely last price—triggers liquidation.
How to Choose Between Margin Modes
Neither mode is universally better. Consider:
- Risk boundary: Should one trade’s collateral be separated?
- Shared strategy: Are positions intended to offset, and are offsets recognized?
- Monitoring: Can you track pool equity, orders, fees and funding?
- Capital exposure: How much collateral could continued losses consume?
- Settings: Could automatic margin addition allocate more funds?
Position size and leverage still matter. No margin mode makes a leveraged position safe.
How to Check or Change Margin Mode on MEXC
On the MEXC futures page, click or tap Isolated or Cross in the order panel, choose a mode and confirm. MEXC’s web and app guides say the “apply to all futures” option does not affect pairs with open positions or orders; those pairs must be handled separately.
MEXC Learn currently states that an existing isolated position can be changed to cross, but not vice versa. Multi-Asset Margin also supports cross only. Review the live confirmation and contract information because rules can change.
Frequently Asked Questions
Is isolated margin safer than cross margin?
Not universally. Isolated margin creates a clearer position-level boundary; cross margin may provide a larger buffer. Either can be liquidated, and additions increase capital exposed.
Can cross margin use my entire account balance?
It may expose all eligible collateral in the applicable pool—not automatically every asset in every MEXC account. Scope depends on the settlement asset, collateral eligibility and account asset mode.
Does switching margin mode change my profit or loss?
No. For an unchanged position, PNL comes from position size and price movement. Margin mode changes its collateral support, liquidation buffer and capital exposure.
Can I switch between cross and isolated margin with an open position?
MEXC currently permits isolated-to-cross changes for an existing position, but not cross-to-isolated changes. Its bulk setting also excludes pairs with open positions or orders. Check the live interface for current restrictions.
How does adding margin affect an isolated position?
It increases supporting equity and generally improves the liquidation buffer, all else equal, but exposes more capital. MEXC’s isolated-only auto-add feature can transfer funds repeatedly as liquidation approaches.
Can one losing position affect other positions in cross margin?
Yes. A loss reduces shared equity and can increase risk for other positions in the pool. The effect depends on other PNL, orders, fees, funding, collateral eligibility and margin rules.
