2. Get your Internal Account ID

When you create a payment order, you must specify which account you want the transaction to originate from. If you are sending someone money, this is the account that the money will be taken out of. If you are charging someone, this is the account that the money will be deposited into.

To get an internal account ID, you can pick one from your internal accounts page, which is here. Any of the IDs will work for testing, although you can refer to Internal Accounts to see the differences in how the test banks process payments.

Or, if you want to hit our API to get all the internal accounts, issue the following API request. You can see the documentation for internal accounts here.

In this example, we are planning to send a payment with the ACH payment type, so let us query for internal accounts that have the capability to send this type of payment.

curl --request GET \
  --url https://app.moderntreasury.com/api/internal_accounts?payment_type=ach
from modern_treasury import ModernTreasury

modern_treasury = ModernTreasury(
  # defaults to os.environ.get("MODERN_TREASURY_API_KEY")

internal_accounts = modern_treasury.internal_accounts.list({
  "payment_type": "ach"

import ModernTreasury from 'modern-treasury';

const modernTreasury = new ModernTreasury({
  apiKey: 'your-api-key', // defaults to process.env["MODERN_TREASURY_API_KEY"]
  organizationId: 'your-organization-id',

async function main() {
  const internalAccounts = await modernTreasury.internalAccounts.list({
    payment_type: 'ach'  


You should have received an array of all your internal accounts that can send payment orders with the payment type "ach". For more information on how we've set up your accounts, see the section under Sandbox Details.

For this quickstart, we'll just use one of the account IDs to originate the payment order from. In this response, we'll use the first one, 0f8e3719-3dfd-4613-9bbf-c0333781b59f.

    "id": "0f8e3719-3dfd-4613-9bbf-c0333781b59f",
    "object": "internal_account",
    "account_type": null,
    "party_name": "Modern Treasury",
    "party_type": null,
    "party_address": null,
    "account_details": [
        "id": "aaf74f7e-d697-4a73-95a3-05bede2edce6",
        "object": "account_details",
        "account_number": "23174905882992971",
        "account_number_type": null,
        "created_at": "2019-11-09T00:11:07Z",
        "updated_at": "2019-11-09T00:11:07Z"
    "routing_details": [
        "id": "a3649136-f8d2-46e8-8b41-327bd7da3110",
        "object": "routing_details",
        "payment_type": null,
        "routing_number": "021000021",
        "routing_number_type": "aba",
        "created_at": "2019-11-09T00:11:07Z",
        "updated_at": "2019-11-09T00:11:07Z"
    "connection": {
      "id": "05487db0-e234-4ae8-914a-c627f76c987f",
      "object": "connection",
      "vendor_id": "example1",
      "vendor_name": "Gringotts Wizarding Bank",
      "created_at": "2019-11-09T00:11:07Z",
      "updated_at": "2019-11-09T00:11:07Z"
    "created_at": "2019-11-09T00:11:07Z",
    "updated_at": "2019-11-09T00:11:07Z"

What’s Next