# How Liquidation Works on Aster: Margin Tiers, the Trigger and a Worked Example (2026) > What Aster does between an under-margined position and a closed one: maintenance margin tiers from the risk endpoint, the mark-price trigger, the IOC step, the insurance fund, ADL, and one BTC long worked to its liquidation price at 20x, 100x and 150x. - Source: https://asterpedia.com/guides/trading/how-liquidation-works-on-aster - Category: trading - Published: 2026-09-15 - Updated: 2026-09-15 - Publisher: Asterpedia (https://asterpedia.com) --- The [fee guide](https://asterpedia.com/guides/fees/aster-fees-explained) tells you what a trade costs. The [1001x guide](https://asterpedia.com/guides/trading/aster-1001x-leverage-explained) tells you how far away liquidation sits as a rule of thumb. Neither explains what actually happens between the moment a position is under-margined and the moment it is gone. This page does, using only what [Aster's documentation](https://docs.asterdex.com) states and what its public endpoints return, and it ends with one BTC position worked to its liquidation price three times so you can see the distance shrink. > **Key takeaway:** Aster liquidates a position when **initial collateral + realized PnL + unrealized PnL falls below the maintenance margin**, measured at the mark price. Maintenance margin is set by the position's notional size through published tiers, not by the leverage you chose. The engine then cancels your orders, tries one immediate-or-cancel reduction, rechecks, and only hands the remainder to the insurance fund at the bankruptcy price if a deficit is left. Every figure below is dated and sourced; Aster changes these parameters, so the live position panel wins over this page. ## What is maintenance margin on Aster? Maintenance margin is the minimum margin a position must keep to stay open. Aster's [margin documentation](https://docs.asterdex.com/trading/perpetuals/margin) says two things about it that matter more than anything else on this page: 1. It is based on the **total size of the position, not the leverage you select**. 2. As position size grows, the higher portions fall into **higher maintenance margin tiers**, each with a progressively higher rate. Leverage decides how much initial margin you post. The formula in the docs is `(position size × mark price) / leverage`. Maintenance margin is a separate number that depends only on notional, so two traders holding the same 10,000 USDT of BTC exposure have the same maintenance margin whether one used 5x and the other used 100x. What differs is how much buffer each has above it. The tiers themselves are not on the liquidation page of the docs, which points readers to a "Trading Rules" page for fee tiers. They are published by the same public risk-bracket endpoint that the [markets hub](https://asterpedia.com/markets) already uses for its leverage caps. Read on September 15, 2026, the BTCUSDT brackets were: | Notional (USDT) | Maintenance margin rate | Maintenance amount | Max leverage in tier | |---|---|---|---| | 0 to 400 | 0.25% | 0 | 200x | | 400 to 300,000 | 0.33% | 1 | 150x | | 300,000 to 800,000 | 0.50% | 512 | 100x | | 800,000 to 3,000,000 | 0.66% | 1,792 | 75x | | 3,000,000 to 12,000,000 | 1.00% | 11,992 | 50x | | 12,000,000 to 70,000,000 | 2.00% | 131,992 | 25x | | 70,000,000 to 100,000,000 | 2.50% | 481,993 | 20x | | 100,000,000 to 230,000,000 | 5.00% | 2,981,993 | 10x | | 230,000,000 to 480,000,000 | 10.00% | 14,481,993 | 5x | | 480,000,000 to 600,000,000 | 12.50% | 26,481,993 | 4x | | 600,000,000 to 800,000,000 | 16.66% | 51,441,993 | 3x | | 800,000,000 to 1,200,000,000 | 25.00% | 118,161,993 | 2x | | 1,200,000,000 to 1,800,000,000 | 50.00% | 418,161,993 | 1x | The "maintenance amount" column is the Binance-style deduction that makes the tiers continuous: maintenance margin = notional × rate − maintenance amount, so a position does not jump in cost the moment it crosses a boundary. Other symbols have their own tables with different rates; a thinner market starts at a higher rate and caps leverage lower, which is why the leverage figure on each [market page](https://asterpedia.com/markets/btc) differs by instrument. > **Info:** The endpoint above answers a POST request with an empty JSON body, not a GET, and Aster does not document it. It is the source the live app reads, and it is the only public place the tiers appear. Aster revises brackets without notice, so treat the table as a snapshot dated September 15, 2026 and confirm the tier for your own size in the app before relying on it. ## At what point is a position liquidated? The trigger is stated in the docs as a single inequality: > Margin = Initial Collateral + Realized PnL + Unrealized PnL < Maintenance margin Three details in the surrounding text change how you should read that line. The first is that unrealized PnL is measured at the mark price. Aster uses the [mark price](https://docs.asterdex.com/trading/perpetuals/fees-and-specs/mark-price), not the last trade, to value open positions and to trigger liquidations. The mark price is the median of three numbers: the volume-weighted spot index adjusted for the funding basis, the index plus a 5-minute moving average of the mid-price basis, and the current contract price. A single wick in the contract price does not liquidate you if the index has not moved; a move in the index can liquidate you even if the last trade on Aster has not printed there yet. The second is that the margin ratio, not the price, is the number to watch. The docs describe liquidation as the point where the risk ratio hits 100% and recommend keeping it below 80%, by adding margin or reducing size. The position panel shows the ratio, the liquidation price and the available balance in real time. The third is that cross and isolated mode behave differently. Aster uses cross margin by default, so every position's collateral and unrealized PnL support every other position; a winning trade elsewhere raises the margin backing a losing one, and a losing one drains it. In isolated mode only the margin assigned to that position counts. In cross mode with hedge trading, a long and a short in the same contract share one liquidation price; in isolated mode they have separate ones. The margin mode cannot be changed once a position or open order exists. The docs also list why the liquidation price shown to you keeps moving: funding payments, changes in collateral value, positions opened or closed elsewhere in the account, and cross-margin effects. Funding is the one people miss. Every settlement lands on the position as realized PnL, so a long on a market where longs have been paying for weeks sees its liquidation price creep up without the price of the asset doing anything. The realized settlements per market, over 30 and 90 days, are on the [Aster funding rate history](https://asterpedia.com/markets/funding-rate-history) page. ## Who closes the position, and what does it cost? Aster's engine does, in a fixed order the docs call a staged, priority-driven process. It is designed to avoid a full close where it can. 1. **Cancel every open order** on the account, so nothing new can interfere with the flow. 2. **Submit one large immediate-or-cancel (IOC) order** to reduce the position. It fills as much as the book allows and the rest is canceled. The intention is to eliminate the margin deficit without closing the whole position. 3. **Recheck margin**, accounting for the realized loss and the liquidation fee. If the remainder meets the maintenance requirement, liquidation stops and what is left of the position stays open. 4. **Bankruptcy and insurance-fund takeover.** If the IOC could not clear the deficit, the leftover is closed at the **bankruptcy price**, the protocol price at which the position's margin is exactly exhausted, and handed to the insurance fund. Any profit or remaining assets from handling it stay with the fund. 5. **Negative balance handling.** If the account is still negative after that, the insurance fund covers the shortfall where it can. If it cannot, auto-deleveraging is triggered against other traders (next section). Two notes from the docs are worth repeating. Smaller positions have less buffer and are more likely to be fully liquidated, because the partial-close step needs room to work; larger positions get the more gradual, tiered treatment. And in extreme volatility the insurance fund may take over a position directly at the bankruptcy price, which can be worse than the normal liquidation price and cost the trader more. On cost, the docs state that liquidation involves the realized loss plus a liquidation fee, that a portion of that fee goes to the insurance fund (it appears in the transaction history as "Insurance clear"), and that the fee is calculated from the applicable liquidation fee rate and the notional of the liquidated position. The liquidation page does not publish the rate. The public `exchangeInfo` endpoint carries a `liquidationFee` field, which read `0.025000` for BTCUSDT and for 593 of the 594 listed symbols on September 15, 2026. Aster's documentation does not define that field, so this page reports the value and stops there rather than turning it into a dollar figure in the example below. The docs' own advice is the practical version: close manually before the maintenance threshold, reduce leverage, or add collateral, because a manual close pays the ordinary [taker fee](https://asterpedia.com/guides/fees/aster-fees-explained) and a liquidation pays more. ## Is there an insurance fund, and what is auto-deleveraging? Both exist and both are documented, so this section can be specific. **The insurance fund** is the account that takes over bankrupt positions and covers negative balances. Its automatic settlement of a negative balance has four conditions, all of which must hold: the negative balance is in a USDT perpetual account, the account has no open positions in either margin mode, the shortfall does not exceed 5,000 USDT, and no funds were transferred in after the liquidation to offset the loss. Outside those conditions the docs direct traders to Discord. The fund is capitalized in part by liquidation fees, and the docs note that positions handed to it may be closed at bankruptcy prices outside the contract's current trading range. **Auto-deleveraging (ADL)** is the last resort when the fund cannot cover a loss in time. The [ADL page](https://docs.asterdex.com/trading/perpetuals/fees-and-specs/auto-deleveraging-adl) says it is triggered when a liquidation cannot be completed before the mark price reaches the bankruptcy price. The engine then reduces opposite-side positions held by other traders, starting with those that are both most profitable and most leveraged. The ranking is published: - PnL percentage = unrealized profit ÷ |position notional| - Effective leverage = |position notional| ÷ (account balance + unrealized profit) - If PnL percentage ≥ 0, ranking = PnL percentage × effective leverage; if negative, ranking = PnL percentage ÷ effective leverage - Leverage-PnL quantile = rank ÷ total user count The higher your quantile, the sooner you are deleveraged. Aster Pro shows it as a four-bar indicator on each position; four bars is high risk. The docs' two ways to reduce it are to lower leverage, or to close and reopen the position, which resets its place in the queue. If you are deleveraged, the position is reduced partially or fully without warning, and you can re-enter afterward. ADL mostly affects traders sitting on large unrealized profits at high leverage, which is to say the traders least expecting to be closed. ## Worked example: one BTC long, three leverage settings The example uses only figures stated above, with the assumptions written down so you can swap in your own. It ignores trading fees and funding, both of which move the real number, and it uses isolated margin so the only collateral is what the position posts. Aster's position panel is the authoritative liquidation price; this is the arithmetic behind it. The position: long 0.1 BTC, entry 100,000 USDT, so notional = 10,000 USDT. That sits in the second BTCUSDT bracket (400 to 300,000 USDT): maintenance margin rate 0.33%, maintenance amount 1 USDT, maximum leverage in the tier 150x. The trigger, written out. Liquidation occurs when initial margin plus unrealized PnL equals maintenance margin. For a long, unrealized PnL at mark price P is 0.1 × (P − 100,000). Maintenance margin at that price is 0.1 × P × 0.0033 − 1. So: ``` IM + 0.1 × (P − 100,000) = 0.1 × P × 0.0033 − 1 IM − 10,000 + 0.1P = 0.00033P − 1 0.1P − 0.00033P = 10,000 − IM − 1 0.09967P = 9,999 − IM P = (9,999 − IM) ÷ 0.09967 ``` Everything now turns on IM, which is notional ÷ leverage. ### At 20x IM = 10,000 ÷ 20 = 500 USDT. ``` P = (9,999 − 500) ÷ 0.09967 = 9,499 ÷ 0.09967 = 95,304.50 ``` Liquidation at about **95,305**, a **4.70%** drop from entry. The rule of thumb says 1 ÷ 20 = 5%; the real distance is shorter because roughly 32 USDT of the 500 posted has to remain as maintenance margin, so only about 468 USDT of it can be lost before the trigger. ### At 100x IM = 10,000 ÷ 100 = 100 USDT. ``` P = (9,999 − 100) ÷ 0.09967 = 9,899 ÷ 0.09967 = 99,317.75 ``` Liquidation at about **99,318**, a **0.68%** drop. The rule of thumb says 1%. Now the gap matters: of the 100 USDT posted, 32 must remain, so the position can absorb only 68 USDT of loss. A third of the buffer the leverage number implies does not exist. ### At 150x, the tier maximum IM = 10,000 ÷ 150 = 66.67 USDT. ``` P = (9,999 − 66.67) ÷ 0.09967 = 9,932.33 ÷ 0.09967 = 99,652.19 ``` Liquidation at about **99,652**, a **0.35%** drop, against a rule-of-thumb 0.67%. Half the implied buffer is maintenance margin. A normal BTC hour can move that far. | Leverage | Initial margin | Buffer above maintenance | Liquidation price | Distance | Rule of thumb | |---|---|---|---|---|---| | 20x | 500 USDT | ~468 USDT | 95,304.50 | 4.70% | 5.00% | | 100x | 100 USDT | ~68 USDT | 99,317.75 | 0.68% | 1.00% | | 150x | 66.67 USDT | ~35 USDT | 99,652.19 | 0.35% | 0.67% | The table leaves out three things that all move the number the same way, against you. Funding settlements land on the position as realized PnL, so on a market where longs have been paying, every settlement moves the liquidation price up by a little (the per-market history is [here](https://asterpedia.com/markets/funding-rate-history)). Trading fees on entry come out of the same collateral before the position has moved at all. And the arithmetic is for isolated margin; in cross mode the whole account balance stands behind the position, which pushes the liquidation price further away and puts everything else in the account at risk in the same move. > **Warning:** These are illustrations of the published formula, not a prediction of where Aster will liquidate you. The tiers, the fee and the mark-price construction all change, and none of the arithmetic accounts for slippage in the IOC step or a takeover at the bankruptcy price. Read the liquidation price in the position panel before and after you open, and again after every funding settlement. ## What happens in 1001x mode? [1001x mode](https://asterpedia.com/guides/trading/aster-1001x-leverage-explained) is a different product with a different liquidation model, and the docs describe it separately. Every 1001x position is isolated: it uses its own margin and losses are limited to that position. Positions trade against the ALP liquidity pool rather than the order book, and there is no bracket table. Instead the [1001x fees page](https://docs.asterdex.com/trading/1001x/fees-and-slippage) gives a closed-form distance: ``` Liquidation price distance = Entry price × (Initial margin × Liquidation loss rate + Cum funding fee) ÷ Initial margin ÷ Leverage Long: Liquidation price = Entry price − distance Short: Liquidation price = Entry price + distance ``` The liquidation loss rate is the share of the initial margin the platform lets a position lose before closing it. Here the docs are inconsistent with themselves, and this page will not pick a number for them: the parameter definition says the default is **90%**, the worked example on the same page uses **85%** (as does a note on the fee page saying the 85% "liquid loss rate" includes the closing fee), and the Degen Mode page states a default of **60%**. Whichever applies to your position is reflected in the liquidation price the app shows. Applying the formula to the same idea as above, a long BTC position with 100 USDT of initial margin at 1001x and no accumulated funding: ``` At a 90% loss rate: distance = 100,000 × (100 × 0.90) ÷ 100 ÷ 1001 = 89.91 → liquidation ≈ 99,910 (0.090% from entry) At an 85% loss rate: distance = 100,000 × (100 × 0.85) ÷ 100 ÷ 1001 = 84.92 → liquidation ≈ 99,915 (0.085% from entry) ``` Under a tenth of a percent, either way. Two more rules from the docs shape what you can do about it. At 500x and above, margin cannot be added to an open position, so the only defense is closing it, and the maximum net profit is capped (around 500% at 500x and 750x, around 300% at 1001x). Below 500x you can add margin from the position row. Funding in 1001x mode accrues every block rather than at fixed settlements, and the docs state that it feeds straight into the liquidation price through the accumulated-funding term above. The docs also note that the dynamic closing fee at the top tiers is included in the loss rate, so there is no separate liquidation fee line to add. ## How to keep a position away from liquidation The docs publish their own list. Here it is, with what each item does to the arithmetic above: - Use lower leverage. It is the only lever that changes the buffer directly: at 20x the position above can lose 468 USDT, at 100x it can lose 68. - Add collateral. This raises IM without changing notional, so the liquidation price moves away. Not available in 1001x mode at 500x and above. - Set a stop loss. A stop that triggers before the maintenance threshold pays the ordinary taker fee instead of the liquidation fee and never meets the IOC step. - Watch funding. On a crowded market the settlements alone erode the buffer; the [funding history](https://asterpedia.com/markets/funding-rate-history) shows how much per month. - Avoid oversized positions. Size pushes you into a higher tier with a higher rate and a lower leverage cap at the same time. - Close before known volatility. Liquidation is a mark-price event, and the mark follows the spot index across several exchanges. None of this is advice on whether to trade, or at what leverage; it is the mechanism, so that the number in the position panel makes sense before you need it to. Aster is a self-custodial venue with no legal entity named in its terms, and this site is an independent guide with a referral relationship, as set out on the [disclaimer](https://asterpedia.com/disclaimer). If you have not placed a first trade yet, the [step-by-step guide](https://asterpedia.com/guides/getting-started/how-to-trade-on-aster) covers the wallet, the deposit and the order ticket, and the [1001x guide](https://asterpedia.com/guides/trading/aster-1001x-leverage-explained) covers the one-click mode in full. ## Frequently asked questions ### At what point is a position liquidated on Aster? Aster's documentation states the trigger as: initial collateral plus realized PnL plus unrealized PnL falls below the maintenance margin. Unrealized PnL is measured at the mark price, not the last trade, so a position is liquidated when the mark price reaches the liquidation price shown in the position panel. Aster recommends keeping the margin ratio below 80% to leave a buffer. ### What is maintenance margin on Aster? Maintenance margin is the minimum margin a position must keep to stay open. On Aster it depends on the position's notional size, not on the leverage you picked: larger positions fall into higher tiers with higher rates. For BTCUSDT the public risk-bracket endpoint reported a 0.25% rate on notional up to 400 USDT and 0.33% from 400 to 300,000 USDT when checked on September 15, 2026, rising in steps to 50% on the top tier, which runs from 1.2 billion to 1.8 billion USDT at 1x. ### Who closes a liquidated position on Aster and what does it cost? Aster's engine does. It cancels every open order on the account, submits one immediate-or-cancel order to reduce the position, rechecks margin, and only if a deficit remains closes the rest at the bankruptcy price and hands it to the insurance fund. Liquidation costs the realized loss plus a liquidation fee, part of which goes to the insurance fund. The docs describe the fee but do not publish the rate on the liquidation page; the public exchangeInfo endpoint reports a liquidationFee field of 0.025 for BTCUSDT. ### Does Aster have an insurance fund and auto-deleveraging? Yes to both, per the documentation. The insurance fund takes over positions that cannot be closed by the IOC step and may cover a negative balance automatically when the account is a USDT perpetual account with no open positions, the shortfall is no more than 5,000 USDT, and no funds were transferred in afterward. If the fund cannot cover the loss, auto-deleveraging reduces the most profitable, most leveraged opposing positions, ranked by a leverage-PnL quantile shown as a four-bar indicator in Aster Pro. ### How does liquidation work in Aster's 1001x mode? Differently. 1001x positions are isolated and trade against the ALP pool rather than an order book. The docs give a formula: liquidation price distance equals entry price times (initial margin times a liquidation loss rate plus accumulated funding), divided by initial margin and by leverage. The docs state the loss rate as 90% by default in one place, use 85% in their worked example, and state 60% for Degen Mode, so check the live position panel. At 1001x on BTC with a 90% rate, the distance is about 0.09% of the entry price.