Portfolio Margin, Explained
How an exchange computes required collateral, and why that choice can double or halve the yield of your strategy.
Margin is the collateral you must deposit to open a leveraged position. The exchange locks it to protect itself: if the market moves against you, that margin absorbs the losses before you get liquidated.
But how is that required collateral calculated? Three very different approaches exist, and portfolio margin is the most sophisticated. For market-neutral strategies (delta neutral, basis trade, arbitrage), the choice of mode can change your yield by a factor of two.
Portfolio margin recognises that two opposite positions hedge each other, so it doesn't demand twice the collateral. It's common sense applied to risk.
Les trois modes de marge
When you open a leveraged position on a perps exchange, one of these three modes applies. The difference: what amount of your capital gets locked as collateral.
Isolated margin
Each position has its own collateral pot, siloed from the others. If the position gets liquidated, you lose that dedicated margin but the rest of your account is intact.
Pro: risk perfectly bounded per position.
Con: no recognition of hedges. If you hold a spot long and a perp short on the same asset, you lock collateral on both sides.
Cross margin
All your positions share a single collateral balance. Losses on one position can be covered by gains on another.
Pro: more efficient than isolated for a multi-position portfolio. Less localised liquidation risk.
Con: a bad position can liquidate the whole account. And crucially, the margin calc remains position by position, no recognition of spot/perp hedges.
Portfolio margin
The system calculates net risk across the whole portfolio, accounting for correlations and hedges. Two opposite positions (long spot + short perp on BTC) are seen as largely neutralising each other, so they require far less collateral than two isolated positions.
Pro: huge capital-efficiency gain for market-neutral strategies.
Con: more complex to grasp, and if one leg fails (e.g. an oracle bug), risk can re-appear suddenly.
If you only run directional plays (long BTC without hedge), the three modes are nearly equivalent collateral-wise. It's for hedged strategies that portfolio margin shines: delta neutral, basis trade, funding arbitrage, options + delta hedge. Anything involving two opposing legs on the same underlying.
Comment un exchange calcule le margin net
A portfolio margin system simulates what would happen to your portfolio under several stressful market scenarios (price moving +/- 10%, vol spiking, etc.) and sets the required collateral to cover the worst case. In broad strokes:
All your BTC positions (spot long, perp short, options, etc.) are grouped into one net exposure. E.g.: +1 BTC spot and -1 BTC perp = 0 BTC net exposed.
The risk engine simulates "what if BTC drops 10%" / "what if BTC rises 15%" / etc. It computes portfolio P&L under each scenario.
The worst scenario yields the maximum potential loss. That figure sets the minimum collateral to lock.
Required margin is recomputed on each significant market move. If your hedge becomes imperfect (one leg drifts), the demanded collateral rises.
Pourquoi c'est si efficace pour le delta neutral
In a classic delta neutral position (1 BTC spot long + 1 BTC perp short), net price exposure is near-zero. When the risk engine simulates price shocks, it sees the portfolio loses very little in every scenario, the two legs offset each other.
Result: required collateral drops drastically compared to an isolated mode where each leg would need its own full margin. In practice, on Hyperliquid, you can often hold a delta neutral position with 30-50% less collateral than in isolated.
If your funding farming yields 10% annualised on $100,000 deployed, but in isolated mode you must lock $200,000 of collateral, your real yield on locked capital is only 5%. In portfolio margin with $110,000 locked, you recover ~9%. Exactly the same gross P&L, but radically different capital efficiency.
Isolated vs Portfolio: the practical gap
Take a standard delta neutral position: 1 BTC spot long at $112,000 + 1 BTC perp short at $112,000. Here's what each mode would require as collateral (indicative orders of magnitude, real parameters depend on the platform).
Spot long: $112,000 fully locked. Perp short at 1x: ~$112,000 of initial margin. Total locked: ~$224,000 for $112,000 of notional per leg.
Same total collateral, but the two positions can rescue each other in case of loss. Total locked: ~$224,000, but reduced liquidation risk.
The risk engine sees the two legs hedging each other. It only requires margin covering the residual risks (basis drift, extreme funding risk, liquidity). Total locked: ~$120,000–140,000 for the same position.
If the position earns $4.37/day of funding, daily yield on locked capital goes from ~0.002% (isolated) to ~0.0035% (portfolio). Almost double.
With $100,000 of initial capital, you can hold roughly $80-90,000 of delta neutral position in portfolio margin, vs $45-50,000 in isolated. You generate almost twice as much funding for the same capital, without raising your directional risk.
Le cas Hyperliquid
Since Unit's integration in 2025, Hyperliquid unifies spot and perps on the same platform, with shared collateral across both markets. Concretely, your spot uBTC counts as collateral for your perp short. No need to fragment your capital across two exchanges. This unification is what makes the delta neutral strategy especially profitable on HL, vs a CEX (spot on Binance) + DEX (perp elsewhere) setup where margin stays siloed.
Les risques du portfolio margin
Portfolio margin is powerful but not free. It rests on a strong assumption: that both legs of your hedge behave as expected. When that assumption breaks, trouble comes fast.
Basis blow-up
If the perp price decouples sharply from spot (bug, manipulation, illiquidity), your "neutral" position can suffer significant losses on the perp leg without the spot compensating. The risk engine then suddenly demands more collateral, often at the worst moment.
Appels de marge soudains
Since required margin is dynamic, a market move can blow up your requirements within minutes. Without a collateral buffer, you can get liquidated even on a "delta neutral" position.
Oracle dependency
Risk calculation uses oracle prices. If an oracle broadcasts a wrong price for a few seconds, you can get wrongly liquidated based on a phantom risk.
Operational complexity
Knowing exactly how much collateral you "really" have available becomes non-trivial. A beginner can open too many positions thinking they have headroom when they're actually at the limit.
Amplified platform risk
You depend entirely on the exchange's risk system. A bug in their engine (bad netting, lax parameters) can create systemic risk you'll suffer from if the platform wobbles.
Keep a safety margin
The golden rule: even when portfolio margin lets you push further, don't use all the available margin. Leave 30-40% buffer to absorb a violent move or a surprise margin call.
Portfolio margin rewards well-built strategies by making their capital efficient. It doesn't turn a bad strategy into a good one. It's a capital amplifier, not a skill amplifier.
To put it into practice
Now that you grasp why portfolio margin is a game-changer, see how it's leveraged concretely in the Delta Neutral guide, or dig deeper into the strategy's fuel in Funding Rates Explained.