> For the complete documentation index, see [llms.txt](https://docs.nomic.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.nomic.io/nbtc/integrating-nbtc-on-evm.md).
# Integrating nBTC on EVM
Nomic supports bridging Bitcoin to EVM-based chains.
## Contract Addresses
Nomic's decentralized custody bridging contract can be found at the following contract addresses:
nBTC on EVM-based chains is issued as an ERC-20 token at the following contract addresses:
Additional network contract addresses will be listed on here in the future, as well as documentation for creating your own customizable deployments in any EVM environment.
## Interchain Deposits
Interchain Deposits allow the generation of Bitcoin addresses which commit to a destination on an EVM-based chain, automatically forwarding any received funds as nBTC to a contract on that chain.
The EVM destination may be either:
* an Ethereum address to receive the nBTC;
* a contract call to be executed with the received nBTC.
Interchain Deposits require communication with [Bitcoin relayers](/network/bitcoin-relayer.md). The set of relayers used by your front-end should be selected with care.
See [`nomic-bitcoin-js`](https://www.npmjs.com/package/nomic-bitcoin) for more information on generating and displaying Bitcoin deposit addresses.
### Withdrawing to Bitcoin
Bitcoin may be withdrawn to a Bitcoin address directly via contract calls on EVM-based chains.
First, `approve` must be called on the token contract (see above table):
```typescript
web3.eth.abi.encodeFunctionCall({
name: 'approve',
type: 'function',
inputs: [
{
type: 'address',
name: 'spender'
},
{
type: 'uint256',
name: 'amount'
}
]
}, [tokenContractAddress, usatAmount]);
```
Next, initiate the withdrawal to a Bitcoin address with a call to the bridge contract:
import { buildDestination } from 'nomic-bitcoin'
let destination = buildDestination({
bitcoinAddress: 'tb1...'
})
web3.eth.abi.encodeFunctionCall({
name: 'sendToNomic',
type: 'function',
inputs: [
{
type: 'address',
name: '_tokenContract'
},
{
type: 'string',
name: '_destination'
},
{
type: 'uint256',
name: '_amount'
}
]
}, [tokenContractAddress, destination, usatAmount]);
---
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