Step 2: Adding a Funding Source

Within Dwolla, the sending party must always verify their bank account in order to be eligible to create a transfer.

Bank Addition and Verification methods

There are three ways of adding a bank to a Customer with the Dwolla API. A simplified table below outlines the similarities and differences of each method.

Bank Addition MethodWill the bank be verified?Required Information
API - Account // Routing NumberOptional - With MicrodepositsBank Account and Routing Number
Dwolla.js - Instant Account VerificationYesOnline Bank Credentials
Third party - PlaidYesOnline Bank Credentials

For an in-depth look at these methods and the features and benefits of each, take a look at our developer resource article.

In this guide, we’ll be utilizing Dwolla’s Instant account verification (IAV) method via dwolla.js for adding and verifying our user’s bank account. Micro-deposit verification can take 1-2 business days to complete, so if speed is a primary factor in your user experience then you may want to feature IAV as your preferred bank verification method.

Step 2A: Adding a bank to the Verified Personal Customer

Next, you will attach a verified funding source for your Customer, which will be done using Instant Account Verification (IAV). This method will give your Customers the ability to add and verify their bank account in a matter of minutes by authenticating with their online banking credentials. Once your Customer reaches the page in your application to add a bank account you’ll ask Dwolla’s server to generate an IAV token.

Generate a single-use IAV token for your Customer (view schema in ‘raw’)

Content-Type: application/vnd.dwolla.v1.hal+json
Accept: application/vnd.dwolla.v1.hal+json
Authorization: Bearer 0Sn0W6kzNicvoWhDbQcVSKLRUpGjIdlPSEYyrHqrDDoRnQwE7Q

HTTP/1.1 200 OK

  "_links": {
    "self": {
      "href": ""
  "token": "lr0Ax1zwIpeXXt8sJDiVXjPbwEeGO6QKFWBIaKvnFG0Sm2j7vL"
$customersApi = new DwollaSwagger\CustomersApi($apiClient);

$fsToken = $customersApi->getCustomerIavToken("");
$fsToken->token; # => "lr0Ax1zwIpeXXt8sJDiVXjPbwEeGO6QKFWBIaKvnFG0Sm2j7vL"
customer_url = ''

# Using DwollaV2 - (Recommended)
customer = "#{customer_url}/iav-token"
customer.token # => "lr0Ax1zwIpeXXt8sJDiVXjPbwEeGO6QKFWBIaKvnFG0Sm2j7vL"
# Using dwollav2 - (Recommended)
customer_url = '''%s/iav-token' % customer_url)
// Using dwolla-v2 -
var customerUrl = '';

  .then(res => res.body.token); // => 'lr0Ax1zwIpeXXt8sJDiVXjPbwEeGO6QKFWBIaKvnFG0Sm2j7vL'

Then, you’ll pass this single-use IAV token to the client-side of your application where it will be used in the JavaScript function dwolla.iav.start. This token will be used to authenticate the request asking Dwolla to render the IAV flow. Before calling this function you’ll want to include dwolla.js in the HEAD of your page.

  <script src=""></script>

Next, you’ll add in a container to the body of your page where you want to render the IAV flow.

<div id="mainContainer">
  <input type="button" id="start" value="Add Bank">

<div id="iavContainer"></div>

Now that you have dwolla.js initialized on the page and the container created where you’ll render the IAV flow, you’ll create a JavaScript function that responds when clicking the “Add bank” button on your page. Once your Customer clicks “Add Bank”, your application will call dwolla.iav.start() passing in the following arguments: the iavContainer element where IAV will render, a string value of your single-use IAV token, and a callback function that will handle any error or response.

<script type="text/javascript">
  $('#start').click(function() {
    var iavToken = 'lr0Ax1zwIpeXXt8sJDiVXjPbwEeGO6QKFWBIaKvnFG0Sm2j7vL';
    dwolla.iav.start(iavToken, {
      container: 'iavContainer',
      stylesheets: [
      microDeposits: false,
      fallbackToMicroDeposits: false
    }, function(err, res) {
      console.log('Error: ' + JSON.stringify(err) + ' -- Response: ' + JSON.stringify(res));

Your Customer will complete the IAV flow by authenticating with their online banking credentials. Go through the IAV flow and add the checking account first.

You’ll know the bank account was successfully added and verified if you receive a JSON response in your callback that includes a link to the newly created funding source. We recommend storing the full URL for future use, as it will be needed for actions such as creating transfers.

Example success callback


Step 2B: Handle Webhooks

If you have an active webhook subscription, you will receive the customer_funding_source_added webhook after the Customer goes through IAV.

On successful verification, you will receive the customer_funding_source_verified webhook.

Step 2C: Add Savings Account

In the steps outlined above, we have walked through how to implement IAV and add a Customer’s checking account. You will want to repeat these steps and add the savings account.

Production: Operational

Financial institutions play an important role in the Dwolla network.

Dwolla, Inc. is an agent of Veridian Credit Union and all funds associated with your account in our network are held in one or more pooled accounts at Veridian Credit Union. These funds may not be eligible for share insurance by the National Credit Union Share Insurance Fund. Dwolla, Inc. is the operator of a software platform that communicates user instructions for funds transfers to Veridian Credit Union.