Plaid Link Auth Flow

Plaid and Prime Trust have partnered to offer platforms, exchanges, and marketplaces a secure way to open and fund accounts. Plaid enables businesses to instantly authenticate a counterparty’s bank account, giving them the ability to retrieve account details directly from the financial institution. Prime Trust provides the building blocks for financial services. With the Account Access APIs, partners can integrate with Prime Trust’s financial infrastructure to open new accounts, send assets into custody and initiate disbursements. Prime Trust supports fast account funding through ACH and additional payment options. As part of the integration, Prime Trust customers can utilize Plaid’s APIs for real-time balance information.

With the Plaid + Prime Trust integration, counterparties can onboard with ease by verifying their accounts in seconds using Plaid Link, a drop-in front-end module. Plaid Link handles input validation, error handling, and multi-factor authentication, providing a seamless onboarding experience to users.

To get started, sign up for Plaid API keys or try out the Plaid demo.

Getting Started

You'll first want to familiarize yourself with Plaid Link, a drop-in integration for the Plaid API that handles input validation, error handling, and multi-factor authentication. You will also need to create or be an existing Prime Trust customer in order to add a bank funding source.

Your customers will use Link to authenticate with their financial institution and select the bank account they wish to use for ACH transactions. From there, you'll receive a Plaid access_token and a Prime Trust processor_token, which allows you to quickly and securely verify a bank funding source via Prime Trust's API without having to store any sensitive banking information. Utilizing Plaid + Prime Trust enables a seamless workflow for sending and receiving payments.

Instructions

Step 1: Set up your Plaid and Prime Trust accounts

You'll need accounts at both Plaid and Prime Trust in order to use the Plaid + Prime Trust integration. You'll also need to enable your Plaid account for the Prime Trust integration.

First, you will need to work with the Prime Trust team to sign up for an Prime Trust account, if you do not already have one.

Next, verify that your Plaid account is enabled for the integration. If you do not have a Plaid account, create one. Your account will be automatically enabled for integration access.

To verify that your Plaid account is enabled for the integration, go to the Integrations section of the account dashboard.

If the integration is off, simply click the 'Enable' button for Prime Trust to enable the integration.

Step 2: Fetch a Link token

A link_token is a one-time use token that is used to initialize Plaid Link. You can create a link_token and configure it for your specific Link flow by calling the /link/token/create endpoint from your server.

Fetch a Link token

Step 3: Integrate with Plaid Link

Integrating with Link is easy. All it takes is a few lines of client-side JavaScript and a small server-side handler to exchange the Link public_token for a Plaid access_token and a Prime Trust processor_token.

Integrate with Link

See the parameter reference for complete documentation on possible configurations.

Plaid.create accepts one argument, a configuration Object, and returns an Object with two functions, open and exit . Calling open will display the "Institution Select" view and calling exit will close Link.

Step 4: Write server-side handler

Plaid’s Link module handles the entire onboarding flow securely and quickly, but does not actually retrieve account data for a user. Instead, the Link module returns a public_token and an account_id (a property on the metadata object) via the onSuccess callback.

This public_token must be exchanged for a Plaid access_token using the /item/public_token/exchange API endpoint. Once you have the access_token for the Item, you'll create a Prime Trust processor_token. You'll send this token to Prime Trust and they will use it to securely retrieve account and routing numbers from Plaid.

You can create valid Prime Trust processor_tokens in the following Plaid API environments:

Server-side handler

const plaid = require('plaid');

// Change sandbox to development to test with live users;
// Change to production when you're ready to go live!
const plaidClient = new plaid.Client({
  clientID: PLAID_CLIENT_ID,
  secret: PLAID_SECRET,
  env: plaid.environments.sandbox
});

// Exchange the public_token from Plaid Link for an access token.
plaidClient.exchangePublicToken(public_token, function(err, res) {
  const accessToken = res.access_token;
  // Create a processor token for a specific account id.
  plaidClient.createProcessorToken(
    accessToken,
    accountId,
    'prime_trust',
    function(err, res) {
      const processorToken = res.processor_token;
    }
  );
});

# Exchange the public token from Plaid Link for an access token.
curl \
  -H 'Content-Type: application/json' \
  -d '{
    "client_id": "PLAID_CLIENT_ID",
    "secret": "PLAID_SECRET",
    "public_token": "PUBLIC_TOKEN"
  }' \
  -X POST \
  https://sandbox.plaid.com/item/public_token/exchange

# Create a processor token for a specific account id.
curl \
  -H 'Content-Type: application/json' \
  -d '{
    "client_id": "PLAID_CLIENT_ID",
    "secret": "PLAID_SECRET",
    "access_token": "ACCESS_TOKEN",
    "account_id": "ACCOUNT_ID",
    "processor": "prime_trust"
  }' \
  -X POST \
  https://sandbox.plaid.com/processor/token/create

require 'plaid'

# Change sandbox to development to test with live users;
# Change to production when you're ready to go live!
client = Plaid::Client.new(env: :sandbox,
                           client_id: PLAID_CLIENT_ID,
                           secret: PLAID_SECRET)

# Exchange the public token from Plaid Link for an access token.
exchange_response = client.item.public_token.exchange(public_token)
access_token = exchange_response.access_token

# Create a processor token for a specific account id.
create_response = client.processor_token.create(access_token, account_id, "prime_trust")
processor_token = create_response.processor_token

// Support Coming Soon

from plaid import Client

# Change sandbox to development to test with live users;
# Change to production when you're ready to go live!
client = Client(
  client_id=PLAID_CLIENT_ID,
  secret=PLAID_SECRET,
  environment='sandbox'
)

# Exchange the public token from Plaid Link for an access token.
exchange_token_response = client.Item.public_token.exchange(public_token)
access_token = exchange_token_response['access_token']

# Create a processor token for a specific account id.
create_response = client.Processor.ProcessorTokenCreate(access_token, account_id, "prime_trust")
processor_token = create_response['processor_token']

For a valid request, the API will return a JSON response similar to:

Processor Token response

{
"processor_token": "processor-sandbox-0asd1-a92nc",
"request_id": "[Unique request ID]"
}

For possible error codes, see the full listing of Plaid error codes.

Step 5: Test with sandbox credentials

Link's sandbox mode is compatible with Plaid's Sandbox API environment. To test the integration in sandbox mode, simply use the Plaid sandbox credentials.

Step 6: Get ready for production

Your account is immediately enabled for our sandbox environment. To move to Production, please request access from the Dashboard. You will want to ensure that you have valid Prime Trust Production credentials prior to verifying bank funding sources in the Prime Trust API with Plaid.

Support and questions

Find answers to many common integration questions and concerns—such as pricing, sandbox and test mode usage, and more—at our Help Center and docs.

If you're still stuck, open a support ticket with information describing the issue that you're experiencing and we'll get back to you as soon as we can.