Multicollateral Margin
Last updated: Jun 1, 2026
Use more than USDT to fund your Synthetix perps account. Deposit supported crypto assets as collateral, trade USDT-settled markets, and manage balances from a single cross-margin account.
Overview
Synthetix supports unified margin. All supported collateral types contribute to your account value, and all perpetual contracts are quoted and settled in USDT.
You can:
- Deposit USDT or supported non-USDT assets
- Trade any market using your combined collateral
- Withdraw each asset separately, subject to margin and debt limits
- Swap non-USDT collateral into USDT when you have USDT debt
Trading fees, funding, and realized PnL are settled in USDT. If your USDT balance goes negative while you have open positions, that is expected.
When you close positions with USDT debt remaining, debt is not repaid automatically. Use Swap to repay voluntarily. If debt limits are breached, the system may convert non-USDT collateral to USDT automatically.
For detailed information on deposits and withdrawals, refer to the Depositing Collateral and Withdrawing Collateral articles.
Supported collateral
| Asset | Type | Notes |
|---|---|---|
| USDT | Stablecoin | Base settlement asset. No haircut. |
| ETH | Native token | Only non-USDT collateral currently supported. Deposited and withdrawn as native ETH. Haircut applies. |
Account health at a glance
Watch these values in your balances table to understand account health:
| Metric | What it tells you |
|---|---|
| Collateral Value | Haircut-adjusted value that counts toward margin (sum drives Adjusted Account Value). |
| Available Margin | Margin available to open or increase positions (USDT row). |
| Unrealized PnL | Open position profit/loss. Can offset negative USDT and extend USDT withdrawals (USDT row). |
| LTV | Current debt ratio per asset when USDT debt exists. Used in withdrawal warnings. |
| LLTV | Maximum debt capacity factor per asset. Contributes to your allowed debt limit. |
| Max Borrow | Tier-based cap on total USDT debt (USDT row). |
How collateral value works
Your margin is based on Adjusted Account Value (AAV), not raw token balances.
USDT
USDT counts at full face value (no haircut).
Non-USDT assets
Non-USDT collateral is valued using:
- Index price - live market price for the asset
- Haircut - a risk discount applied to the asset's USD value
The Collateral Value shown in your balances table is the haircut-adjusted amount that counts toward margin. Hover the value to see the breakdown: asset value, haircut rate, and final collateral value.
Tiered haircuts
Haircuts depend on the USD value of each asset in your account. Synthetix uses tiered rates, but with current per-account deposit limits (shown as Max. Account Deposit when you deposit), most users sit in the first tier. Check Collateral Value in your balances table (hover for haircut %) for your actual margin contribution.
When collateral prices move
Non-USDT collateral is marked to index price. If ETH falls, your Collateral Value and Adjusted Account Value drop - even if your position PnL is unchanged. That reduces Available Margin, can raise LTV, and increases liquidation or auto-exchange risk. Monitor collateral prices, not just position PnL.
Example: You hold 5 ETH at $3,000 with a 10% haircut. Collateral Value ≈ $13,500. If WETH drops 20% to $2,400, Collateral Value falls to ≈ $10,800 - a $2,700 margin reduction with no trade activity.
USDT debt
Your USDT balance can go negative during normal trading:
- Trading fees
- Funding payments
- Realized/Unrealized losses on closed trades
This negative balance is USDT debt. It is backed by your non-USDT collateral
| Situation | What happens |
|---|---|
| Open positions, negative USDT, positive UPNL covers it | Allowed - not treated as debt. Swap not available. |
| Open positions, negative USDT, UPNL does not fully cover | USDT debt exists - backed by collateral. LTV caps and Swap apply. |
| Close positions with USDT debt remaining | Debt is not auto-repaid. Use Swap voluntarily, or forced auto-exchange if debt exceeds allowed limit. |
| Debt exceeds allowed limit | Forced auto-exchange converts non-USDT collateral to USDT |
| Winning position, negative USDT | Positive UPNL can support USDT withdrawals and may eliminate effective debt. |
Fees (collateral-related)
| Action | Fee |
|---|---|
| Withdraw | Per-asset withdrawal fee - deducted from amount received. Shown before you confirm. |
| Swap (voluntary) | Exchange fee based on the asset's lowest-tier haircut. Shown in the swap quote before you confirm. |
| Auto-exchange (forced) | Higher exchange fee than voluntary Swap (approximately 2× the voluntary rate). Applied automatically - no confirmation step. |
| Deposits & on-chain actions | Ethereum gas paid in ETH. Not charged on trades or swaps. |
Swap (voluntary collateral exchange)
Use Swap on any non-USDT balance row to convert collateral into USDT.
When it's available: You have USDT debt (negative USDT not fully covered by positive UPNL). If you have no debt - even if USDT shows negative while a winning position backs it - Swap is not needed and may be unavailable.
How it works:- Select the source asset and amount.
- Review the estimated USDT received after fees.
- Confirm. Collateral is sold and you receive USDT minus a fee.
Tip: Swapping to repay debt improves account health and can restore withdrawable margin, even when withdrawable amounts appeared near zero before the swap.
Auto-exchange
Auto-exchange converts non-USDT collateral to USDT without manual action. It protects the protocol and keeps accounts solvent.
When forced auto-exchange runs
Forced auto-exchange runs automatically during account health checks when your USDT debt exceeds your allowed debt limit.
Allowed debt is the lower of:
- Sum of (each non-USDT asset's Collateral Value × its LLTV)
- Your tier's Max Borrow
When breached, the system sells non-USDT collateral until debt is back within limits.
How assets are chosen
The system sells assets with the lowest haircut first (deterministic tie-break by asset name when haircuts are equal). Forced exchanges use a higher fee rate than voluntary Swap.
LLTV and LTV
| Term | Meaning |
|---|---|
| LTV (Loan-to-Value) | Your current USDT debt ÷ total non-USDT collateral value (adjusted). Shown per asset row when you have debt. |
| LLTV (Liquidation LTV) | Maximum LTV before forced auto-exchange for that asset. Shown in the balances table. |
| Max Borrow | Maximum USDT debt allowed for your tier. |
If LTV reaches LLTV, collateral is auto-exchanged until LTV returns to zero.
Example (WETH, LLTV 80%): If your debt is 80% or more of your non-USDT collateral value, WETH may be sold to USDT automatically at best available prices minus the forced-exchange fee.
Balances table reference
| Column | Description |
|---|---|
| Asset | Collateral token |
| Balance | Quantity held |
| Last Price | Current index price |
| Total Equity | Raw USD value (quantity × price) |
| Collateral Value | Haircut-adjusted value used for margin |
| LLTV | Liquidation LTV threshold for the asset |
| LTV | Current debt ratio (when USDT debt exists) |
| Available Margin | Margin available for new trades (USDT row) |
| Unrealized PnL | Open position PnL (USDT row) |
| Max Borrow | Tier-based USDT debt cap (USDT row) |
| Actions | Deposit, Withdraw, Swap |
Sub-accounts
Each sub-account holds its own collateral balances. You can deposit non-USDT assets directly to a sub-account without holding USDT there.
- Margin is per sub-account - collateral in one sub-account does not support positions in another.
- Transfers between sub-accounts follow the same withdrawable rules as withdrawals (margin budget, USDT cap, LTV cap).
- Choose the correct sub-account before depositing - collateral is not shared across sub-accounts.
Liquidation
If Adjusted Account Value falls below maintenance requirements, the liquidation engine may take over the account.
Typical sequence:
- Margin breach - account no longer meets maintenance margin (MMR) for open positions.
- Position action - open positions may be partially or fully closed, or transferred to SLP accounts.
- Collateral transfer - all collateral types are transferred to designated SLP accounts.
- Debt resolution - auto-exchange may run as part of account health checks before or during liquidation.
Maintaining healthy LTV, sufficient Collateral Value, and buffer above maintenance margin reduces liquidation risk. Collateral price drops count toward liquidation even without trading activity.
FAQ
Can I trade without holding USDT?
Yes. Deposit supported non-USDT collateral and trade USDT-settled markets. Fees and PnL still settle in USDT, so your USDT balance may go negative while positions are open.
Why is Swap unavailable when my USDT is negative?
Your USDT can show negative while positive unrealized PnL covers it - that is not debt. Swap only appears when you have USDT debt after UPNL is applied.
Why is my collateral value lower than balance × price?
Non-USDT assets have haircuts. The collateral value column shows the amount that actually counts toward margin after the haircut is applied.
Why can't I withdraw all my USDT when I also hold ETH?
USDT withdrawals are capped at your held USDT plus positive unrealized PnL. ETH collateral value supports margin and trading but does not increase the USDT you can withdraw unless you swap or sell the ETH first.
Why did my margin drop without closing a trade?
Non-USDT collateral is marked to index price. A price drop reduces Collateral Value and Adjusted Account Value, even if your position PnL is unchanged.
Why is my max withdrawal zero even though I have a balance?
Common reasons:
- Open positions reserve margin
- USDT debt requires collateral to stay in the account (LTV cap)
- The asset is fully backing debt with no spare margin budget
Try closing or reducing positions, swapping collateral to USDT to repay debt, or depositing additional collateral.
What's the difference between Collateral Value and Total Equity?
Total Equity = quantity × index price. Collateral Value = haircut-adjusted amount that counts toward margin. Only Collateral Value affects trading limits and liquidation.
Will closing my last position repay my USDT debt?
No. Realized PnL settles into USDT, but remaining debt stays until you Swap or collateral is auto-exchanged if limits are breached.
What's the difference between Swap and Withdraw?
Withdraw sends tokens to your wallet. Swap converts non-USDT collateral to USDT inside your account to repay debt. Swap is only available when you have USDT debt.
Why was my collateral sold without me clicking Swap?
Forced auto-exchange runs when USDT debt exceeds your allowed limit. Monitor LTV and Max Borrow, maintain buffer collateral, use voluntary Swap to repay debt, or reduce position size.
Does auto-exchange require my approval?
No. Forced auto-exchange runs automatically when triggers are hit. You can reduce the chance of forced exchange by monitoring LTV, maintaining extra collateral, using voluntary swap to repay debt, or reducing position size.
Why did my USDT go negative overnight?
Funding payments and trading fees settle in USDT. If you hold non-USDT collateral and no spare USDT, your USDT balance can go negative.
Are gas fees charged on swaps?
No. Gas is required for on-chain deposits and withdrawals only.