Fees and minimums

Each deposit is charged on its own, and the callback tells you exactly what happened: value_coin is the deposit, fee_coin is everything charged and value_forwarded_coin is what reached your payout address.

value_forwarded_coin = value_coin - fee_coin

What is charged

• Service fee: a percentage of the deposit, rounded up to the smallest unit of the asset once, and never less than the minimum service fee. It is capped at the deposit.
• Network fee: a fixed amount per forwarding transaction, charged in the asset itself. When the deposit is too small it is the network fee that shrinks first.
• fee_coin in callbacks and logs is the sum of both. fee_percent in logs is the service fee rate as a percent.

All arithmetic uses integer units of the asset, so amounts are exact. A deposit whose fees leave nothing to forward cannot be paid out automatically, which is why the minimum is always set above the maximum possible fee. Create and info answer 503 with Ticker is temporarily unavailable if a ticker's minimum does not cover its fees.

Minimums

Every ticker has a minimum deposit, returned as minimum_transaction_coin by create and info. Show it to the payer before they send.

• A deposit of at least the minimum is forwarded, each deposit separately.
• A deposit below the minimum is not forwarded, triggers no callback, does not appear in the logs and is not paid out.
• The minimum that counts is the one in force when the deposit was first detected. A later change does not affect deposits already detected.

Default fee schedule

Mainnet default fees

Testnet default fees

To budget the network side, GET /{ticker}/estimate/ returns a conservative ceiling of the forwarding cost in the chain's native coin. It is a fee cap, not a quote of what is deducted from your deposit.