Link a bank with Aerosync

Aerosync is a bank aggregator that allows a user to connect with both the largest FIs and local credit unions across the U.S. It supports bank OAuth flows for fast connections and quick balance refresh.

Step 3A - Retrieve an Aerosync widget URL & token

HTTP request

Sandbox - GET https://api.sandbox-pay.aero.inc/v2/aggregatorCredentials?aggregator=aerosync

Production - GET https://api.aeropay.com/v2/aggregatorCredentials?aggregator=aerosync

Note the aggregator query parameter setting Aerosync as the aggregator your user will link their bank with.

Code Example - Request

Make a request to Aeropay's GET /v2/aggregatorCredentials endpoint. You'll need to input aerosync as the value for the aggregator query parameter.

curl --request GET  
     --url '<https://api.sandbox-pay.aero.inc/v2/aggregatorCredentials?aggregator=aerosync'>  
     --header 'Content-Type: application/json'  
     --header 'accept: application/json'  
     --header 'authorization: Bearer {{userForMerchant token}}'

Code Example - Response

{
    "fastlinkURL": "dev.aerosync.com",
    "token": "eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJqdGkiOiIwMzU1OWEyZi05NDdhLTQzNDQtOTY3Zi0xYjhlMzRkMjBlZTYiLCJleHAiOjE3NTM4MTQxMTMsInVzZXJJZCI6IjM2ZGU4ZGM5MTIxODQ2ZjNiNWE4MDU5ODU5NWEwMTc0IiwiY29ubmVjdGlvbklkIjoiMzZkZThkYzkxMjE4NDZmM2I1YTgwNTk4NTk1YTAxNzQiLCJ1c2VyUGFzc3dvcmQiOiIyMTM0MTViYTZiZmU0ZGQ4OTllOTgyZmFiNjE4NDBhNCIsIkNsaWVudElkIjoiMjRjZDdmMTktYmNjOS00NjVkLTllNTMtODg1NzRhMWFkNzBmIiwiQ2xpZW50TmFtZSI6IlFBX3Rlc3QgMDUtMjAtMjUiLCJzZXNzaW9uSWQiOiJhMzc0NDY5NjZmZTE0NWIyOGUzMTc5MDQ1NDRhMzJkZSJ9.YlPmaJA0KmJWrzz9GxftCtVehtWuh-KZTjoqVsobC4A",
    "username": "36de8dc9121846f3b5a80598595a0174"
}

👍
Keep note of the token from the response. You'll need it for the next step.

Step 3B - Load the Aerosync widget

Follow one of the guides to initialize and launch the Aerosync widget within your application. These guides also explain how to interact the widget and it's postMessage events:

📘
Sandbox: Aerosync OTP bypass
In sandbox, the OTP challenge behavior during bank linking depends on the configurationId used to initialize the Aerosync widget:

Without your designated configurationId: a real OTP will be sent and must be entered to proceed.

With your designated configurationId: no real OTP is sent. Enter 0000 to proceed through the challenge.

If the 0000 bypass is not working with your configurationId, reach out to your Solutions Engineer to confirm your bypass configuration.
This behavior is sandbox-only and has no effect in production.

📘
For a full integration guide on Aerosync, check out our Guide
Aerosync Developer Implementation Guide

👍
Keep note of the connectionId returned from the widget's onSuccess() event. You'll use them for the next step.

Code Example - Widget Response

 {  
    "connectionId": "a2c7f64f-3df9-4090-b3bd-ad6fc3003c90",  
    "clientName": "Patrice's Pizza"
    "aeroPassUserUuid": "735e33b9-78ec-4887-99d7-a3056997ceb9"  
  }

Step 3C - Connect bank account to Aeropay

Now that a user has connected their bank account with Aerosync - the next step is to link that bank account to Aeropay. You'll need to make a request to Aeropay's POST /v2/linkAccountFromAggregator endpoint.

HTTP request

Sandbox - POST https://api.sandbox-pay.aero.inc/v2/linkAccountFromAggregator Production - POST https://api.aeropay.com/v2/linkAccountFromAggregator

Request parameters

Parameter	Required?	Type	Description
connectionId	Yes	String	This value is returned from the Aerosync widget.
aggregator	Yes	String	`aerosync`

Code Example - Request

curl --request POST  
     --url <https://api.sandbox-pay.aero.inc/v2/linkAccountFromAggregator>  
     --header 'Content-Type: application/json'  
     --header 'accept: application/json'  
     --header 'authorization: Bearer {{token}}'  
     --data '  
{  
  "connectionId": "a2c7f83f-4df9-4090-b3bd-ad6fc3003c90",  
  "aggregator": "aerosync"  
}

Code Example - Response

{
    "userBankInfo": {
        "bankAccountId": 4351,
        "bankName": "Aerosync Bank (oAuth)",
        "accountLast4": "0191",
        "name": "Aerosync Savings",
        "externalBankAccountId": "None",
        "isSelected": true,
        "accountType": "savings",
        "status": "verified",
        "createdDate": "2025-08-04T21:26:53+00:00",
        "accountHolderInfo": [
            {
                "name": {
                    "fullName": "Dwight Schrute"
                }
            }
        ],
        "canFetchBalance": true,
        "balance": 312425
    }
}

🚧
We prefer that each individual User has their own bank account.
For couples with joint bank accounts, they can reach out to support at Aeropay to get their shared bank account added to each of their individual Aeropay accounts.
Alternatively, the couple can choose to share a User account.