# Deposit and Join

This section outlines the process to deposit tokens into a Bancor liquidity pool and join the rewards program in a single transaction.

This process reduces gas costs and ensures your tokens are earning the maximum available yield.

### 1. Approve

In order for the contract to interact with the tokens in your wallet and perform the transaction, an *`Approval`* must be set first for the contract.

{% hint style="info" %}
If you wish to deposit ETH or have already set approval for a very large amount for the token, skip to [step 3](#3.-function-depositandjoin).
{% endhint %}

* Visit the relevant token contract. \
  This can be found on Etherscan by searching for the token ticker, or by clicking the Etherscan link on Coingecko token pages. \
  For example: [BNT](https://etherscan.io/token/0x1f573d6fb3f13d689ff844b4ce37794d79a7ff1c#writeContract) | [DAI](https://etherscan.io/token/0x6b175474e89094c44da98b954eedeac495271d0f#writeContract) | [LINK](https://etherscan.io/token/0x514910771af9ca656af840dff83e8264ecf986ca#writeContract)
* Connect your wallet as explained in "[Using Etherscan](https://docs.bancor.network/guides/bancor-etherscan-guide/broken-reference)"
* Execute the `Approve` function (this is a Write function)

<table data-header-hidden><thead><tr><th width="220"></th><th></th></tr></thead><tbody><tr><td>_spender</td><td>The address of the <em><code>StandardRewards</code></em> <a href="broken-reference">found here</a></td></tr><tr><td>_value</td><td>The amount you would like to approve (it can be identical or larger than the amount you wish to deposit, BUT NOT LESS) in <code>WEI</code> format as <a href="broken-reference">explained here</a></td></tr></tbody></table>

![](https://273705617-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FC9gDtGR2KNhur3c7qIJR%2Fuploads%2Fwd4dY60fjcJIrTeYlVQF%2Fimage.png?alt=media\&token=1d002cc6-1da0-47bb-ab92-01a2b2c9c459)

* Click `Write` to sign the *`Approve`* in your wallet

### 2. Function latestProgramId()

In order to join the latest rewards program, you first need to identify the token's **program ID**.

* Visit the *`StandardRewards`* contract [on etherscan](https://etherscan.io/address/0xb0B958398ABB0b5DB4ce4d7598Fb868f5A00f372#readProxyContract)
* Execute the `latestProgramId` function (this is a Read function)

![](https://273705617-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FC9gDtGR2KNhur3c7qIJR%2Fuploads%2FQ5g8Q8sqrIXwMahUsOWg%2Fimage.png?alt=media\&token=9fa02ef2-f818-4c56-b033-b55a2369d6c3)

`Input variable`

| Name | Type  | Description                                  |
| ---- | ----- | -------------------------------------------- |
| pool | Token | The address of the token you wish to deposit |

{% hint style="info" %}
For ETH use *0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE*
{% endhint %}

`Output response`

| Name | Type    | Description                                                                |
| ---- | ------- | -------------------------------------------------------------------------- |
| id   | uint256 | The unique identifier for the latest program available for the input token |

{% hint style="info" %}
You will require the id value for the depositAndJoin function.
{% endhint %}

### 3. Function depositAndJoin()

{% hint style="danger" %}
Some pools might be in deficit which might effect the ability to withdraw the full amount you have deposited ([more info](https://blog.bancor.network/market-conditions-update-june-19-2022-e5b857b39336)).
{% endhint %}

Now that you know the program ID and have the approval in place, you are ready to deposit your tokens into the Bancor pool and rewards contracts.&#x20;

Execute the **depositAndJoin** function, with the id you received from the first step, and the number of tokens you wish to deposit.&#x20;

* Visit the *`StandardRewards`* contract [on etherscan](https://etherscan.io/address/0xb0B958398ABB0b5DB4ce4d7598Fb868f5A00f372#writeProxyContract)
* Execute the *`depositAndJoin`* function (this is a Write function)

![](https://273705617-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FC9gDtGR2KNhur3c7qIJR%2Fuploads%2FPiwoosYSiQA3KTIGgdP3%2Fimage.png?alt=media\&token=0e4f1316-96d6-4f84-bf6c-edb3eecf3f36)

| Name           | Type    | Description                                                                                                                                                                            |
| -------------- | ------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| depositAndJoin | uint256 | <p>Note:<br>IF ETH, indicate the ETH amount in full units (10.5 ETH should be indicated as 10.5)<br>For any other token, this should be set to 0</p>                                   |
| id             | uint256 | <p>The unique identifier for the latest program available for the input token <br>(extracted in <a href="#2.-function-latestprogramid">step 2</a>)</p>                                 |
| tokenAmount    | uint256 | The token (i.e BNT, ETH, DAI, LINK) amount you would like to deposit (using `WEI` format [explained here](https://docs.bancor.network/guides/bancor-etherscan-guide/broken-reference)) |

Once executed successfully, the following will happen:

1. Your tokens will be deposited into the Bancor pool
2. The protocol will generate bnTokens that represent your position in the pool, and automatically stake them into the rewards contract