Partner Fee Collectors

Symbiosis automatically charges protocol-level cross-chain fees and deducts gas fees for intermediate chains during the execution of cross-chain operations. The fee withholding logic is described in Symbiosis & Fees

To support partner integrations, Symbiosis provides two dedicated fee collector contracts that allow partners to charge and collect custom fees in addition to the standard protocol fees:

• General Fee Collector: deployed on the Symbiosis chain (the protocol host chain) — used for all cross-chain operations except those to and from the Bitcoin network.

• BTC Fee Collector: deployed on the BNB Chain — used for operations to and from the Bitcoin network.

General Fee Collector

• Contract Address: address

• Fee Token: sTokens (e.g., sUSDC, sUSDT, sWETH, etc.) Symbiosis utilizes sTokens to facilitate cross-chain operations. Each sToken is a 1:1 pegged representation of an asset on its corresponding native chain and can be bridged back to that chain at any time. For more information about sTokens, refer to Symbiosis sTokens and Supported Chains

• Collecting Address and Fee Parameters The General Fee Collector contract is administered by the Symbiosis team. To enable custom fee collection, partners must contact Symbiosis to configure the following parameters:

  • Fee recipient address (partnerAddress) — the address authorized to withdraw collected fees from the contract.

  • Fee model — percentage-based, fixed amount, or a combination of both,

  • Fee value — the actual percentage and/or fixed amount to be charged.

• Collecting Fees To apply your fee configuration during cross-chain operations, the fee recipient address (partnerAddress) must be included in the SwapRequestSchema when calling the Symbiosis API. If this address is omitted, no custom fee will be collected during the operation.

• Fee Management Methods

  To interact with the fee collector contract the following methods can be used:

  • collectedFees() – Returns the total fees collected.

  • claimFee() – Withdraws accumulated fees to the configured payout address.

Additional Notes on Fee Collection

Custom fees collected through the General Fee Collector are accumulated in approximately 120 synthetic assets (sTokens) on the Symbiosis chain.

Partners must manually call the withdrawal method for each token type to claim their collected fees. After withdrawal, the tokens need to be bridged to their respective native networks. This process can be somewhat time-consuming due to the number of assets involved.

To simplify this, an automation script will soon be provided. The script will:

• Aggregate all collected fees,

• Convert them into a single target token, and

• Bridge the resulting amount to the designated destination network.

BTC Fee Collector

• Contract address: address

• Fee Token: syBTC (address) syBTC is a 1:1 BTC-pegged token that can be exchanged on EVM-compatible networks or bridged back to native Bitcoin.

• Collecting Address and Fee Parameters The BTC Fee Collector contract is administered by the Symbiosis team. To enable custom fee collection, partners must contact Symbiosis to configure the following parameters:

  • Fee recipient address (partnerAddress) — the address eligible to withdraw collected fees from the contract.

  • Fee model — percentage-based, fixed amount, or a combination of both,

  • Fee value — the actual percentage and/or fixed amount to be charged.

• Collecting Fees To apply your fee configuration during swaps to or from BTC, the fee recipient address (partnerAddress) must be included in the SwapRequestSchema when calling the Symbiosis API.

  If this address is omitted, no custom fee will be collected during the operation.

• Fee Management Methods

  To interact with the fee collector contract the following methods can be used:

  • collectedFees() – Returns the total fees collected.

  • claimFee() – Withdraws accumulated fees to the configured payout address (method ID: 0x6ebc51e1).