Sandbox: Transfers

Overview

Transfers move funds to external addresses, other Coinbase users, or payment methods. In Sandbox, all transfers are simulated—webhooks fire and status transitions occur, but no real transactions happen.

Prerequisites

Before you begin, you need cdpcurl, a Sandbox API key, and a funded account. See the Quickstart for instructions.

1. Simulate transfer by target type

Set your account ID:

export ACCOUNT_ID="account_db458f63-..."

Get your account ID

cdpcurl -k $CDP_API_KEY \
  'https://sandbox.cdp.coinbase.com/platform/v2/accounts' | sed '1d' | jq -r '.accounts[].accountId'

a. To reserved addresses

You can use any valid address format for the network—it doesn’t need to be a real or funded address. Use reserved addresses below to test specific error scenarios.

Use these reserved addresses to test specific success and failure scenarios:

Any funds sent in production to these addresses will be lost. In Sandbox, they are simulated and used for testing purposes only.

Reserved Address	Simulated Outcome
`0x1111111111111111111111111111111111111111`	Success
`0x2222222222222222222222222222222222222222`	Transfer invalid target
`0x3333333333333333333333333333333333333333`	Invalid address
`0x4444444444444444444444444444444444444444`	Unsupported network

Success
Transfer invalid target
Invalid address
Unsupported network

Below is a simulation using 0x1111... to test successful transfer handling:

cdpcurl -k $CDP_API_KEY \
  -X POST \
  -d "{
    \"source\": {
      \"accountId\": \"$ACCOUNT_ID\",
      \"asset\": \"usdc\"
    },
    \"target\": {
      \"network\": \"base\",
      \"address\": \"0x1111111111111111111111111111111111111111\",
      \"asset\": \"usdc\"
    },
    \"amount\": \"5.00\",
    \"asset\": \"usdc\",
    \"execute\": true
  }" \
  'https://sandbox.cdp.coinbase.com/platform/v2/transfers'

You should expect: HTTP 2xx with normal transfer response

Below is a simulation using 0x2222... to test malformed target error handling:

cdpcurl -k $CDP_API_KEY \
  -X POST \
  -d "{
    \"source\": {
      \"accountId\": \"$ACCOUNT_ID\",
      \"asset\": \"usdc\"
    },
    \"target\": {
      \"network\": \"base\",
      \"address\": \"0x2222222222222222222222222222222222222222\",
      \"asset\": \"usdc\"
    },
    \"amount\": \"5.00\",
    \"asset\": \"usdc\",
    \"execute\": true
  }" \
  'https://sandbox.cdp.coinbase.com/platform/v2/transfers'

You should expect: HTTP 400

{
  "errorType": "invalid_request",
  "errorMessage": "'target' is invalid: must match one of [Account, Payment Method, Onchain Address, Email Instrument]. Account requires 'accountId'; Payment Method requires 'paymentMethodId'; Onchain Address requires 'network'; Email Instrument requires 'email'"
}

Below is a simulation using 0x3333... to test invalid address error handling:

cdpcurl -k $CDP_API_KEY \
  -X POST \
  -d "{
    \"source\": {
      \"accountId\": \"$ACCOUNT_ID\",
      \"asset\": \"usdc\"
    },
    \"target\": {
      \"network\": \"base\",
      \"address\": \"0x3333333333333333333333333333333333333333\",
      \"asset\": \"usdc\"
    },
    \"amount\": \"5.00\",
    \"asset\": \"usdc\",
    \"execute\": true
  }" \
  'https://sandbox.cdp.coinbase.com/platform/v2/transfers'

You should expect: HTTP 400

{
  "errorType": "invalid_request",
  "errorMessage": "Invalid onchain address for network base."
}

Below is a simulation using 0x4444... to test invalid network parameter handling:

cdpcurl -k $CDP_API_KEY \
  -X POST \
  -d "{
    \"source\": {
      \"accountId\": \"$ACCOUNT_ID\",
      \"asset\": \"usdc\"
    },
    \"target\": {
      \"network\": \"base\",
      \"address\": \"0x4444444444444444444444444444444444444444\",
      \"asset\": \"usdc\"
    },
    \"amount\": \"5.00\",
    \"asset\": \"usdc\",
    \"execute\": true
  }" \
  'https://sandbox.cdp.coinbase.com/platform/v2/transfers'

You should expect: HTTP 400

{
  "errorType": "invalid_request",
  "errorMessage": "base is not a supported network."
}

The target address can be any valid format for the network—it doesn’t need to be a real or funded address. Use reserved addresses to test specific scenarios.

b. To reserved email addresses

Send to a Coinbase user by email. In Sandbox, only whitelisted test emails work:

Test Email	Description
`testuser1@domain.com`	Returns successful validation
`testuser2@domain.com`	Returns successful validation

Get your account ID

cdpcurl -k $CDP_API_KEY \
  'https://sandbox.cdp.coinbase.com/platform/v2/accounts' | sed '1d' | jq -r '.accounts[].accountId'

cdpcurl -k $CDP_API_KEY \
  -X POST \
  -d "{
    \"source\": {
      \"accountId\": \"$ACCOUNT_ID\",
      \"asset\": \"usd\"
    },
    \"target\": {
      \"email\": \"testuser1@domain.com\",
      \"asset\": \"usd\"
    },
    \"amount\": \"5.00\",
    \"asset\": \"usd\",
    \"execute\": true
  }" \
  'https://sandbox.cdp.coinbase.com/platform/v2/transfers'

Any email not in the whitelist returns a 4xx error. This prevents privacy concerns around validating real email addresses in Sandbox.

c. To reserved payment methods

For testing fiat withdrawals to external banks (Fedwire, SWIFT), see the Payment Methods guide. Payment methods have pre-built test scenarios for different use cases (e.g., active vs inactive methods).

2. Validate before executing

Use validateOnly: true to verify recipient details (like email addresses or crypto addresses) before executing a transfer.

Get your account ID

cdpcurl -k $CDP_API_KEY \
  'https://sandbox.cdp.coinbase.com/platform/v2/accounts' | sed '1d' | jq -r '.accounts[].accountId'

cdpcurl -k $CDP_API_KEY \
  -X POST \
  -d "{
    \"source\": {
      \"accountId\": \"$ACCOUNT_ID\",
      \"asset\": \"usd\"
    },
    \"target\": {
      \"email\": \"testuser1@domain.com\",
      \"asset\": \"usd\"
    },
    \"amount\": \"5.00\",
    \"asset\": \"usd\",
    \"validateOnly\": true
  }" \
  'https://sandbox.cdp.coinbase.com/platform/v2/transfers'

A 2xx response means the transfer would succeed. A 4xx response includes an errorType explaining why validation failed.

Use the reserved addresses from section 1.a to test validation scenarios for crypto addresses (e.g., validate with 0x3333... to test invalid address handling).

3. List transfers

View all transfers for your account:

cdpcurl -k $CDP_API_KEY \
  'https://sandbox.cdp.coinbase.com/platform/v2/transfers'

Example response

{
  "transfers": [
    {
      "transferId": "transfer_8b707d29-4690-4948-b645-de1cd1f5fd05",
      "status": "completed",
      "source": {
        "accountId": "account_db458f63-418a-4a91-a045-fab93ac35c3f",
        "asset": "usd"
      },
      "target": {
        "paymentMethodId": "paymentMethod_398435cb-03bd-5568-b8d5-44accd7ce305",
        "asset": "usd"
      },
      "sourceAmount": "5",
      "sourceAsset": "usd",
      "targetAmount": "5",
      "targetAsset": "usd",
      "createdAt": "2026-02-11T23:19:24.086Z",
      "updatedAt": "2026-02-11T23:19:24.183Z"
    }
  ]
}

Create Transfer

API reference for creating transfers

List Transfers

API reference for listing transfers

CDP PAYMENTS API

REST API

Overview

Prerequisites

1. Simulate transfer by target type

a. To reserved addresses

b. To reserved email addresses

c. To reserved payment methods

2. Validate before executing

3. List transfers

What to read next

Create Transfer

List Transfers

CDP PAYMENTS API

REST API

​Overview

​Prerequisites

​1. Simulate transfer by target type

​a. To reserved addresses

​b. To reserved email addresses

​c. To reserved payment methods

​2. Validate before executing

​3. List transfers

​What to read next

Create Transfer

List Transfers

Overview

Prerequisites

1. Simulate transfer by target type

a. To reserved addresses

b. To reserved email addresses

c. To reserved payment methods

2. Validate before executing

3. List transfers

What to read next