Overview
Some blockchain networks require a minimum number of confirmations and only allow a specific maximum number of confirmations.
Minimum number of confirmations
EVM-compatible blockchains
All EVM-compatible blockchain networks require a minimum of 1 confirmation. You cannot enter 0 confirmations for these blockchain networks.
Maximum number of confirmations
Specific blockchain networks have a maximum number of confirmations.
| Blockchain name | Maximum # of confirmations |
| For most newly supported assets see Blockchain data sheets on Fireblocks | |
| Cronos | 1 |
| Morph | 1 |
| Peaq | 1 |
| Xion | 1 |
| Initia | 2 |
| Gevolut | 2 |
| Humanity | 2 |
| Fastex | 3 |
| WorldMobile | 3 |
| TRON | 20 |
| 0G | 30 |
| Abstract | 30 |
| Aleph Zero | 30 |
| Apechain | 30 |
| Arbitrum | 30 |
| Arbitrum Testnet | 30 |
| Avalanche | 30 |
| Avalanche Testnet | 30 |
| Babylon | 30 |
| Berachain | 30 |
| Binance Smart Chain | 30 |
| Binance Smart Chain Testnet | 30 |
| Bob | 30 |
| Boom | 30 |
| CELO | 30 |
| CELO Testnet ALF | 30 |
| CELO Testnet BAK | 30 |
| Codex | 30 |
| Coinbase | 30 |
| eCredits Testnet | 30 |
| Ethereum Testnet Holesky | 30 |
| Ethereum Testnet Hoodi | 30 |
| Ethereum Testnet Sepolia | 30 |
| EthereumPoW | 30 |
| Fantom | 30 |
| Filecoin | 30 |
| Flare | 30 |
| Flow | 30 |
| Gunzilla | 30 |
| HederaEVM | 30 |
| HOM Testnet | 30 |
| HT Chain | 30 |
| HT Chain Testnet | 30 |
| HyperEVM | 30 |
| Ink | 30 |
| Iotex | 30 |
| Kaia | 30 |
| Katana | 30 |
| KUB Bitkub | 30 |
| KUB Bitkub Testnet | 30 |
| Lisk | 30 |
| Lumia | 30 |
| Manta | 30 |
| Mirasmanda | 30 |
| Moonbeam | 30 |
| Moonriver | 30 |
| Neutron | 30 |
| Oasys | 30 |
| OP Mainnet (Optimism) | 30 |
| Plume | 30 |
| Ronin | 30 |
| RSK Smart Bitcoin | 30 |
| RSK Scroll | 30 |
| SEP | 30 |
| Shimmer | 30 |
| Smart Bitcoin Testnet | 30 |
| Smart BCH Testnet | 30 |
| Somnia | 30 |
| Soneium | 30 |
| Songbird | 30 |
| Songbird Legacy | 30 |
| Sonic | 30 |
| TAC | 30 |
| Viction | 30 |
| Wirex | 30 |
| XinFin | 30 |
| zkSync | 30 |
| Cosmos Hub | 100 |
| Injective | 100 |
| Celestia | 100 |
| Ethereum | 100 |
| NEAR | 100 |
| Polygon | 300 |
| Polygon Mumbai | 300 |
| Polygon zkEVM | 300 |
| Ethereum Classic | 1200 |
| Ethereum Classic Testnet | 1200 |
Blockchains with a finality property
Blockchain finality refers to the point at which a transaction or block is considered irreversible and permanently recorded on the blockchain. This means that once finality is achieved, the transaction cannot be altered, reversed, or removed, providing certainty and security for users and applications.
Some blockchains have a built-in finality property, which means they do not rely on a variable number of confirmations to achieve this state; instead, transactions are finalized after a set process or threshold is met.
Examples of blockchains with a finality property include Solana, which requires only one confirmation for a transaction to be considered final, as well as others, visible in the list below. These networks are designed so that once a transaction is confirmed according to their finality rules, it is effectively immutable and protected from reversion or double-spending attacks.
The following blockchains have a rigid finality property, which is non-changeable (i.e., you cannot change the confirmation policy for them):
| Asset | Finality property | Description |
| For most newly supported assets see Blockchain data sheets on Fireblocks | ||
| ALGORAND | 1 | |
| ATOM | 1 | |
| INJECTION | 1 | |
| CELESTIA | 1 | |
| CRONOS | 1 | |
| EOS | 2 | |
| HBAR | 1 | |
| HUMANITY | 2 | |
| KAVA | 2 | |
| KUSAMA | 2 | |
| LINEA | 2 | |
| MORPH | 1 | |
| POLKADOT | Confirmed: 1 Finalized: 2 |
|
| RIPPLE | 1 | |
| SOL | Confirmed: 1 Finalized: 2 |
Event confirmed |
| STABILITY | 1 | |
| STELLAR | 1 | |
| TERRA | 2 | |
| TEZOS | 2 | |
| TON | 1 | |
| WorldMobile | 3 | |
Using minimums and maximums for speed and security
If you're an advanced user, we recommend you modify the base number of confirmations to match your organization's requirements for its overall safety strategy and faster, more efficient trading.
Transfers between vault accounts
For transfers between your Fireblocks vault accounts, you can apply 0 confirmations to all assets. Since your vault accounts are under your direct management, you are more likely to submit the correct amounts.
Deposits from external sources to your Vault
For deposits from external wallets to your Fireblocks vault, apply a high number of confirmations for all assets to establish a higher level of certainty about the transaction. The trade-off is that transactions take longer to complete.
Alternatively, you can choose to set higher confirmation values for select assets of a particular blockchain. Some examples of higher-than-default values that align with some blockchain networks' confirmation behavior are:
- All assets on Bitcoin Cash (BCH): 6
- All assets on Bitcoin SV (BSV): 30
- All assets on Bitcoin (BTC): 3
- All assets on Dash (DASH): 3
- All assets on Ethereum Classic (ETC): 500
- All assets on Ethereum (Ethereum Proof-Of-Stake or ETH): 60 (ETH PoS 60 confirmations pertain to the number of blocks registered in the chain within a 2-epoch timeframe, which is the chain's finality period)
- All assets on Ethereum Proof-Of-Work (ETHW): 30
- All assets on Litecoin (LTC): 6
- All assets on Solana (SOL): 1
To find the right balance between speed and finality confidence, we only mark confirmed blocks as completed. Confirmed blocks are backed by votes from the majority of validators and have a very low probability of being reverted. Based on our analysis, a reversion has never happened before. - USDC asset on Avalanche (AVAX): 7
- USDC asset Ethereum (ETH): 6
- All assets on ZCash (ZEC): 12
- All assets on XDC Network (XDC, formerly XINFIN): 30