How tiers affect margin
Initial margin is based on position size, mark price, and the max leverage available at that size:initial_margin = position_notional / max_leverage
If a fill increases your total position size into a lower-leverage range, Phoenix recalculates margin for the full resulting position, not only the newest fill.
Reducing position size can lower margin because:
- the notional position is smaller
- the remaining size may qualify for higher max leverage
Resting orders
Risk-increasing resting limit orders can also reserve margin before they fill. Phoenix evaluates whether resting bids or asks could increase exposure. If they can, the account may need additional collateral even though the orders have not executed yet. Reduce-only orders do not add exposure.Live tier values
Leverage tiers are market-specific and can change. Use Market Parameters for current tier values, including:- max leverage
- max size
- limit order risk factor