Fireblocks now sets the gas limit of an EVM transfer from a vault account to an exchange based on the destination address, instead of a fixed multiplier, so fee estimates are more accurate.
What changed
Every EVM transaction has a gas limit, which is the maximum amount of network work the transaction can use. Fireblocks estimates the gas limit before it sends the transaction, and your vault account needs enough of the base asset to cover the fee that the limit implies.
Previously, Fireblocks applied a fixed multiplier of 2.6 times the estimated gas to every EVM transfer from a vault account to an exchange. The multiplier existed to cover exchanges that use smart contract deposit addresses. Most exchanges now use standard deposit addresses, so the fixed multiplier overestimated the gas. In some cases it required you to hold more than twice the base asset that the transfer needed.
Fireblocks now calculates the gas limit from the type of the destination address, not from a fixed multiplier.
What this means for you
- More accurate estimates. The base asset balance that Fireblocks requires for the fee is closer to what the transfer needs.
- Fewer failed transfers. Over-funding the base asset to avoid insufficient funds errors on exchange transfers is less necessary.
- Lower fee overhead. A gas limit sized to the transfer reduces unnecessary fee overhead, which is most noticeable on networks with higher fees.
Who this affects
The change applies to EVM assets, such as ERC-20 tokens like USDT, sent from vault accounts to exchange destination addresses. You don't need to change any setting or take any action.
The article EVM fees: Fee behavior lists a fixed multiplier of 2.6 times the estimated gas for transfers to an exchange. That multiplier no longer applies to transfers from a vault account to an exchange.
If a transfer fails for insufficient funds
Fees for token transfers are paid in the base asset of the blockchain, from the same vault account that sends the tokens. If an exchange transfer fails with an insufficient funds substatus, check the base asset balance of the source vault account. To keep vault accounts funded automatically, use the Gas Station.