BYDFi cross margin: why the leverage you pick does not set your liquidation price

Here is what the page says and why it matters.

The screenshot above is the public BYDFi liquidation FAQ, showing the cross vs isolated explanation and the effective leverage example.

What triggers liquidation on BYDFi

The FAQ uses the maintenance margin rate (MMR) as the risk indicator. When it reaches or exceeds 100%, the system triggers liquidation. The reference price for this is the fair price, not the last traded price. BYDFi says using fair price helps reduce unnecessary liquidations from abnormal or short-term moves, and you can switch the chart between fair price, last price and index price to watch all three.

Isolated margin: leverage matters directly

In isolated mode, if you do not add margin after opening, higher leverage puts the liquidation price closer to your entry price. That is the intuition most people already have, and in isolated mode it holds.

Cross margin: leverage mostly decides how much margin is locked

BYDFi's example is simple. You have 10 USDT in the account and open a 10 USDT position at 10x.

• Initial margin = position value / leverage = 10 / 10 = 1 USDT. That 1 USDT is locked and 9 USDT stays available.
• Because the position is cross margin, the whole futures account balance supports it.
• Effective leverage = account balance / position value = 10 / 10 = 1.

So even though the slider says 10x, the account is effectively at 1x. BYDFi concludes that in cross margin the liquidation price is mainly driven by the available account margin and the value of open positions, not by the leverage number you selected.

The flip side

The same logic works against you. In cross margin every position shares the same balance. A losing trade on one contract eats the margin that supports all the others, and adding a new position uses up some of the cushion. Your liquidation price can move even if the contract you are watching has not.

What happens when MMR hits 100%

BYDFi describes a ladder rather than an instant full close:

1. Order cancellation. In cross margin all open orders in the account are cancelled; in isolated mode with auto-margin addition on, orders for that contract are cancelled.
2. Long-short self trading. In cross margin only, if you hold both a long and a short, the system reduces them against each other.
3. Tiered liquidation. If the position sits in a higher risk-limit tier, part of it is liquidated at the bankruptcy price to drop it to a lower tier, then the margin rate is recalculated.
4. Full liquidation. If it is already at the lowest tier and MMR is still at or above 100%, the liquidation engine takes over the rest at the bankruptcy price.

The FAQ adds that the bankruptcy price will not show up in your transaction records or on the chart, because the liquidation engine handles it, not the matching engine. Liquidated orders appear under Position History.

A practical checklist

1. Decide which mode you are in before thinking about leverage. The same slider means different things in cross and isolated.
2. In cross margin, look at effective leverage, total balance against total position value, rather than the selected multiple.
3. Watch the fair price line, not only the last price candle.
4. Remember that cross margin cancels all open orders in the account during liquidation, including ones on other pairs.
5. Larger positions sit in higher risk tiers with higher maintenance margin rates.

The takeaway

On BYDFi, leverage is a direct liquidation lever in isolated mode, but in cross mode it mostly decides how much margin gets locked. The real number to watch is your maintenance margin rate against fair price, and in cross mode that depends on the whole account.

Do you trade cross or isolated, and did the effective leverage idea change how you size?