Fees on Sai

Sai charges some of the lowest trading fees in the perpetual futures market. Taker fees start at a 0.05% base rate, and no fee is taken out for deposits or withdrawals. When factoring in zero gas costs and available discounts, Sai is one of the most competitive exchanges for active futures traders.

Trading Fee Reference

Fee Type	Rate	Description
Taker Fee	0.05% (Base Rate)	Charged on the total position size for taker orders.
Taker Fee with Referral	0.0425%	The default and minimum referral code discount on Sai is 15% of trading fees.
Gas Fees for Trading	0 (Free)	Always zero on Sai’s L1, Nibiru.
Trigger Fee	0.01%	Charged only on automated orders (Limit, Stop Loss, Take Profit) to pay for the execution cost.
Deposits & Withdrawals	0 (*)	Always zero on Sai’s L1, Nibiru. However, gas is required to bridge before depositing.
Maker Fee	0 (Free)	No fee is charged for maker orders.
Borrowing Fee (Funding Rate)	Variable, based on open-interest skew	A time-based fee on open positions that contribute to a long or short OI imbalance. The market header shows the current hourly rate. See Borrowing Fees.
Rapid-Close Fee	Up to ~1.15% of position size on most markets, decaying to 0 by ~12 min	Extra closing fee on positions held only briefly; paid to LPs. Some protected markets use a higher peak rate. See Rapid-Close Fee.

Standard trading fees are calculated based on your total position size (leverage × collateral), not just your wallet balance.

Contents

• Fees on Sai
• Trading Fee Reference
• Key Concepts
• Where Fees are Distributed
• Fee Lifecycle
  • 1. Opening a Trade
  • 2. Closing a Trade
• Borrowing Fees (Funding Rate) for Open Interest Skew
• Rapid-Close Fee
• Liquidation Mechanics
  • Key Difference: Collateral vs. Position
  • The Liquidation Penalty
  • Priority of Payments (The “Waterfall”)
  • Liquidation Example
• Insufficient Collateral
• Borrowing fee calculation reference

Key Concepts

• Base Fees: Every trade has base percentages for taker, maker, and conditional (trigger) orders.
• Fee Multipliers: The base fees are adjusted by two multipliers:
  1. Tier-based: High-volume traders earn points, which unlock a lower fee multiplier.
  2. Referral: Referred traders receive a discount multiplier.
• Effective Multiplier: The lowest of the applicable multipliers is used to calculate the final fee.
• Liquidation Fees: These are a fixed percentage of the collateral and are not subject to the multipliers.

Where Fees are Distributed

• The Vault (LPs): Receives 25% of all Closing Fees to support platform stability and reward Liquidity Providers for their risk.
• The Protocol (Gov): Receives the remaining 75% of Closing Fees and 100% of Open Fees. A portion of these fees is allocated to a pool for governance stakers.
• Referrers: Earn a percentage of the fees generated by their referees from the governance staker portion.
• Keepers (Bots): Receive 20% of the Trigger Fee for executing automated orders (Limit, Stop Loss, Take Profit); the remaining 80% goes to the Protocol.

Fee Lifecycle

1. Opening a Trade

When a user opens a trade, the system performs the following steps to calculate and process fees:

1. Determine Multiplier: It fetches the trader’s fee tier and checks for a referral discount to find the effective fee multiplier.
2. Calculate Fees: The system calculates the adjusted open and trigger fees by applying the effective multiplier to the base fees.
3. Deduct and Distribute: The total fee is deducted from the trader’s collateral and distributed. A portion goes to the trigger service provider (if applicable), a cut is allocated to the referrer, and the net amount is added to a pool for governance stakers.

2. Closing a Trade

When a user closes a trade, fees are handled differently depending on whether it’s a normal closure or a liquidation.

• Normal Closure: The system determines the effective multiplier, calculates adjusted close fees, and distributes them.
• Liquidation: The fee is a fixed percentage of the trader’s collateral, bypassing any fee tier or referral discounts. This fee is then split between the vault and governance stakers.

Borrowing Fees (Funding Rate) for Open Interest Skew

Borrowing fees are a time-based charge on open leveraged positions when long and short open interest (OI) become unbalanced. The Sai market header labels the current hourly borrowing rate as Funding Rate.

If long OI is greater than short OI, long positions can accrue the fee. If short OI is greater, short positions can accrue it. Sai checks the imbalance for both the individual market and its borrowing group. The rate grows as the relevant imbalance takes up more of the available OI limit, and it can fall to zero when long and short OI are balanced.

This is different from a peer-to-peer funding payment. Sai deducts the fee from the position that owes it. Traders on the less crowded side do not receive that fee.

Estimate the cost

The fee applies to position size, which is collateral multiplied by leverage. To estimate the charge, multiply the position size by the displayed hourly rate and the number of hours held.

For example, $100 of collateral at 10x leverage creates a $1,000 position. At an illustrative rate of 0.01% per hour, holding it for five hours costs about $0.50:

Input	Value
Collateral	$100
Leverage	10x
Position size	$1,000
Hourly rate	0.01%
Holding time	5 hours
Estimated borrowing fee	$0.50

The rate is not locked when you open the trade. It changes as OI changes, so this example is an estimate rather than a quote.

When the fee is charged

Borrowing fees accrue block by block while the position is open. Accrued fees reduce the position’s equity and move its liquidation price closer, even before settlement. Sai deducts the accrued amount when the position closes or changes size or leverage.

For the accumulator logic and contract data structures, read the Perp: Borrowing Fees.

Rapid-Close Fee

Sai adds an extra fee when a position is closed very soon after it opens. The fee is largest in the first seconds of a trade and decays smoothly to zero the longer the position is held. It reaches zero after about 12 minutes, so it never touches positions held past that window.

The fee protects Liquidity Providers. Very short holds can capture the brief difference between the on-chain oracle price and the live market price at the Vault’s expense; a higher fee on the fastest closes removes that edge while leaving ordinary trading untouched.

How it is calculated

The fee is a percentage of your position size (leverage × collateral). The rate decays exponentially with the time the position is held:

fee_rate(hold) = F0 × e^(−hold / τ)

• F0 is the peak rate at the moment of opening (1.15% on the global curve).
• τ (tau) sets how fast the rate decays (about 76 seconds).
• The rate is forced to zero once a position is held past 300 blocks, or about 12 minutes.
• The charge is capped at 50% of the collateral being closed.

With the global curve the fee is approximately:

Hold time	Fee (of position size)	Example at 10×	Example at 50×
0 seconds	1.15%	11.5% of collateral	capped at 50%
~1 minute	~0.51%	~5.1% of collateral	~25.7% of collateral
~2 minutes	~0.23%	~2.3% of collateral	~11.5% of collateral
~3 minutes	~0.10%	~1.0% of collateral	~5.1% of collateral
~5 minutes	~0.02%	~0.2% of collateral	~1.0% of collateral
~7 minutes	~0.004%	~0.04% of collateral	~0.2% of collateral
~12 minutes or longer	0	0	0

Because the rate applies to position size, higher leverage makes the same short hold cost a larger share of your collateral. The fee is added to the standard closing fee and is paid entirely to the Vault (LPs). Fee-tier and referral discounts do not reduce it.

When it applies

The fee applies to voluntary closes and to Take-Profit / Stop-Loss closes, including partial closes and leverage reductions. Liquidations and after-hours risk reductions are exempt.

Most markets share the global curve. A few protected markets carry a higher peak rate F0 of 2.117%, because a larger per-update price move gives a larger short-hold edge. The protected markets are SUI, ADA, DOGE, HYPE, and ZEC. They use the same decay speed, 300-block window, and 50% collateral cap as the global curve. The live rate for any market is queryable on-chain (see Verifying Info Onchain).

What this means for traders

Holding a position for a few minutes or longer makes this fee negligible or zero. Opening and closing within the same minute incurs a meaningful extra fee on close that is largest in the first seconds and falls quickly as the hold grows. In on-chain queries and trade events this fee is labelled the short-lived-trade penalty.

Liquidation Mechanics

Liquidation occurs when your remaining collateral can no longer safely support your open position. At that point, the protocol force-closes the trade to protect the vault from bad debt.

Key Difference: Collateral vs. Position

Standard trading fees are based on position size. Liquidation fees are different: they are calculated from your remaining collateral at the time the position is liquidated. Fee-tier and referral discounts do not apply.

The Liquidation Penalty

When a position is liquidated, a 10% liquidation penalty is applied to the remaining collateral. The penalty is split into two equal components:

1. Closing Component (5% of Collateral):

   • Compensates the system for closing the position.
   • Split: 20% goes to the Vault; 80% goes to the Protocol.

2. Trigger Component (5% of Collateral):

   • Rewards the liquidator or keeper that triggered the liquidation.
   • Split: 20% goes to the Liquidator; 80% goes to the Protocol.

Priority of Payments (The “Waterfall”)

If a user is liquidated and their collateral is nearly empty (insufficient to cover the full fees), the smart contract pays out in a specific priority order to protect the system:

1. First Priority → The Vault: The Vault gets its share first to ensure Liquidity Providers are protected.
2. Second Priority → The Liquidator: The bot gets its reward next.
3. Third Priority → The Protocol: The Government receives whatever is left.

Liquidation Example

You are liquidated while you have $100 of collateral remaining.

• Total Penalty Calculation: $10.00 (10% of $100).
• Distribution:
  • $1.00 goes to the Vault (20% of the Closing portion).
  • $1.00 goes to the Liquidator (20% of the Trigger portion).
  • $8.00 goes to the Protocol.
• Outcome: The liquidation fee is paid from your remaining collateral. The rest of your collateral is used to settle the forced closure, and your position collateral is zeroed.

Insufficient Collateral

If a trader’s collateral is not sufficient to cover fees and losses, the fees are still accounted for in the internal ledgers (e.g., for governance and referrers) but are not physically transferred from the trader’s collateral. The losses are absorbed by the Protocol Vault.

Borrowing fee calculation reference

Sai tracks separate borrowing-fee accumulators for each market and borrowing group. At either level, the accumulator for the side with more OI changes by:

rate_delta =
  fee_per_block
  × elapsed_blocks
  × (abs(long_oi - short_oi) / max_oi) ^ fee_exponent

The formula uses these inputs:

• fee_per_block is the configured base rate for one block.
• elapsed_blocks is the number of blocks since the accumulator last updated.
• long_oi and short_oi are the long and short open interest.
• max_oi is the OI limit for the market or borrowing group.
• fee_exponent controls how sharply the rate rises as the skew approaches the OI limit.

When long and short OI are equal, rate_delta is zero. Otherwise, only the accumulator for the side with more OI increases at that level.

For each period in a trade’s lifetime, the contract compares the market-level and borrowing-group fee deltas for the trade’s direction and uses the larger one. If a market changes borrowing groups, the contract keeps each period’s history and adds the applicable deltas together.

The final charge uses the accumulated rate delta and the position size:

borrowing_fee = accumulated_rate_delta × collateral × leverage

The Funding Rate in the market header converts the current per-block rate into an hourly estimate. It does not lock the rate for the life of the trade.

Verifying Info Onchain

Claim: Default referral code discount on trading is 15%.

Query the perp contract’s raw state for the storage key referree_base_fee_multiplier:

# Sai Mainnet Perp Smart Contract
PERP='nibi1ntmw2dfvd0qnw5fnwdu9pev2hsnqfdj9ny9n0nzh2a5u8v0scflq930mph'
NODE='https://rpc.nibiru.fi:443'

KEY_HEX="$(printf referree_base_fee_multiplier | xxd -p -c 256)"

nibid query wasm contract-state raw "$PERP" "$KEY_HEX" \
  --node "$NODE" \
  --output json

Result:

{"data":"IjAuMTUi"}

Then decode the base64 value:

printf 'IjAuMTUi' | base64 -d

Output:

"0.15"

The storage item is the referral discount amount. Here “0.15” means a 15% discount.

Claim: The rapid-close fee curve is configured on-chain.

Query the perp contract for the live curve:

# Sai Mainnet Perp Smart Contract
PERP='nibi1ntmw2dfvd0qnw5fnwdu9pev2hsnqfdj9ny9n0nzh2a5u8v0scflq930mph'
NODE='https://rpc.nibiru.fi:443'

nibid query wasm contract-state smart "$PERP" \
  '{"get_short_lived_penalty_curve":{}}' \
  --node "$NODE" --output json

Result:

{"data":{"f0":"0.0115","tau_blocks":"31","max_window_blocks":300,"cap_pct":"0.5"}}

f0 is the global peak rate (0.0115 = 1.15%), tau_blocks the decay constant in blocks, max_window_blocks the hold past which the fee is zero (300 blocks ≈ 12 minutes at ~2.44s/block), and cap_pct the cap as a fraction of collateral (0.5 = 50%). To preview the rate for a specific market and hold time, query get_short_lived_penalty_rate with a market_index and hold_blocks.

Protected markets can override the global peak rate. To verify the effective F0 for a market:

nibid query wasm contract-state smart "$PERP" \
  '{"get_short_lived_penalty_f0_for_market":{"market_index":43}}' \
  --node "$NODE" --output json

Market 43 (HYPE) currently returns:

{"data":"0.02117"}