# GET /v4/referral/code

_Merkl API_

Returns the transaction to register user as a referrer on-chain and some additional state using chainId, referralKey, and address query parameters

### Query parameters

- `chainId` (number) _(required)_
- `referralKey` (string) _(required)_
- `address` (string) _(required)_

## Example request

```bash
curl -X GET "https://api.merkl.xyz//v4/referral/code?chainId=<chainId>&referralKey=<referralKey>&address=<address>" \
  -H "x-api-key: YOUR_API_KEY"
```