> ## Documentation Index
> Fetch the complete documentation index at: https://docs.anchorage.com/llms.txt
> Use this file to discover all available pages before exploring further.

# On-chain interactions

> Bridge assets and interact with on-chain protocols.

export const Check = () => <Icon icon="check" color="#049159" />;
export const Cross = () => <Icon icon="x" color="#dd0000" />;

## STRK bridging

Bridge STRK tokens between Ethereum and Starknet using the Anchorage Digital iOS app or web dashboard.

### Before you start

Ensure the following before initiating a bridge:

* You have a wallet on the destination chain within the same organization.
* The source wallet has sufficient funds to cover gas fees:
  * **Bridging from Ethereum**: The Ethereum wallet must have enough ETH to pay for gas.
  * **Bridging from Starknet**: The Starknet wallet must have enough STRK\_STARKNET to pay for gas fees.

<Info>
  Upon first use of the bridging feature, you will be prompted to accept the Protocol Connectivity Terms of Service.
</Info>

### Bridge STRK from Ethereum to Starknet

This operation converts your STRK (ERC-20) tokens on Ethereum to native STRK\_STARKNET tokens on Starknet. It involves two steps: authorizing a spender, then initiating the bridge.

#### Step 1: Authorize spender (first-time setup)

Before your first bridge, you must authorize the bridge contract as a spender. This sets a total allowance that each bridge transaction draws from.

<Steps>
  <Step title="Navigate to your STRK wallet">
    Navigate to your vault and select the wallet holding STRK on Ethereum.
  </Step>

  <Step title="Select Authorize Spender">
    On iOS, the **Authorize spender** button is located alongside the other action buttons on the wallet screen. On web, select the **Actions** dropdown, then choose **Authorize spender**.
  </Step>

  <Step title="Enter the authorization amount">
    Enter the total amount of STRK you want to authorize for bridging. This is a cumulative limit, not a per-transaction amount.
  </Step>

  <Step title="Review and approve">
    Review and approve the operation. Once the quorum policy is met, the authorization is signed and broadcast on-chain.
  </Step>
</Steps>

<Note>
  You only need to authorize a spender once, as long as your remaining allowance covers the amount you want to bridge. If you exhaust your allowance or want to change it, repeat this step with a new value. To revoke authorization entirely, set the authorized amount to 0.
</Note>

#### Step 2: Bridge to Starknet

Once the spender is authorized:

<Steps>
  <Step title="Select Bridge to Starknet">
    From the same STRK wallet on Ethereum, select **Bridge to Starknet**. On iOS, this button is located alongside the other action buttons on the wallet screen. On web, select the **Actions** dropdown, then choose **Bridge to Starknet**.
  </Step>

  <Step title="Enter the bridge amount">
    Enter the amount of STRK you'd like to bridge. This amount must be less than or equal to your remaining authorized allowance.
  </Step>

  <Step title="Review and submit">
    Review the operation details, optionally add a comment, then submit. Once the quorum policy is met, the operation is signed and broadcast on-chain.
  </Step>

  <Step title="Receive tokens on Starknet">
    After the transaction is confirmed on Ethereum, the bridged STRK\_STARKNET tokens are deposited into your Starknet wallet. This typically takes a few minutes to complete.
  </Step>
</Steps>

### Bridge STRK from Starknet to Ethereum

This operation converts your STRK\_STARKNET tokens on Starknet to STRK (ERC-20) tokens on Ethereum.

<Steps>
  <Step title="Navigate to your STRK_STARKNET wallet">
    Navigate to your vault and select the wallet holding STRK\_STARKNET on Starknet.
  </Step>

  <Step title="Select Bridge to Ethereum">
    Select **Bridge to Ethereum**. On iOS, this button is located alongside the other action buttons on the wallet screen. On web, select the **Actions** dropdown, then choose **Bridge to Ethereum**.
  </Step>

  <Step title="Enter the bridge amount">
    Enter the amount of STRK\_STARKNET you'd like to bridge.
  </Step>

  <Step title="Review and submit">
    Review the operation details, optionally add a comment, then submit. Once the quorum policy is met, the bridge operation is signed and broadcast on-chain.
  </Step>

  <Step title="Receive tokens on Ethereum">
    After the transaction is initiated on Starknet, the bridged STRK (ERC-20) tokens are automatically deposited into your Ethereum wallet. This process typically takes 4–8 hours.
  </Step>
</Steps>

### Bridge summary

|                                | Ethereum → Starknet          | Starknet → Ethereum          |
| ------------------------------ | ---------------------------- | ---------------------------- |
| **Source token**               | STRK (ERC-20)                | STRK\_STARKNET               |
| **Destination token**          | STRK\_STARKNET               | STRK (ERC-20)                |
| **Gas token required**         | ETH (on Ethereum)            | STRK\_STARKNET (on Starknet) |
| **Authorize spender required** | <Check /> (first-time setup) | <Cross />                    |
| **Estimated completion time**  | \~Minutes                    | \~4–8 hours                  |
| **Available on**               | iOS and Web                  | iOS and Web                  |