Frequently Asked Questions

APIs (Application Programming Interfaces) allow systems and apps to share information with each other in real time.

BMO APIs let you connect your accounting, treasury management and other financial systems to your Online Banking for Business accounts. That connection gives you access to your real-time banking activity and lets you make transactions directly in the programs you use every day – without having to export data, upload files, or sign in to Online Banking for Business. You can also use our APIs to build your own features to integrate our banking services directly within your own applications and platforms. Our APIs make your banking data work for you.

BMO APIs let you access and use your account data and payment services whenever and wherever you want. Clients like you are using our APIs to:

• See real-time balances for all accounts
• Retrieve day-end, month-end and year-end balances for all accounts
• Pull transaction histories
• Review transactions based on a specific set of criteria
• Replace BAI files and other settlement reports and processes
• Retrieve images of deposited cheques and other items
• Validate third-party accounts before creating transactions
• Send or collect payments
• Process in-app purchases and fund digital wallets
• Receive real-time payment status updates by API, email or text message.

Once you create an account on the BMO Developer Portal, you can:

• Add and manage access for your team members
• Explore our APIs and detailed documentation
• Use our API Explorer to try our APIs and get sample request code
• Access your Sandbox credentials for your applications
• Generate Sandbox access tokens
• Connect your applications directly to our Sandbox
• Request access to our Pre-Production environment
• Manage test data for Pre-Production testing
• Request access to Production environment

If you're an Online Banking for Business customer, you can use our APIs to connect your BMO accounts and create payments right from your accounting, treasury management and other financial systems.

You can safely experiment with our APIs in our Sandbox and test them in our Pre-Production environment at no cost. When you’re ready to launch your application, please contact us to discuss pricing.

To explore our APIs in the Sandbox and Pre-Production environments, you'll need to apply for an organization account on the BMO Developer Portal. Once we've reviewed and approved your application, we'll send you an email with your account credentials and instructions for adding your team members.

When you apply and are approved for an organization account, we'll send you two emails: one with setup details and one with a link to create a password. If you don't see these emails, please check your spam folder. If you still can't find them, please contact us.

To try our Sandbox in your own application, you'll need an API key. This API key, along with the Client ID and Client secret displayed under "My applications", can be used directly in your application to communicate with our Sandbox environment. Depending on your language preferences, you can choose between an API key for English code responses and one for French responses.

Once you have your API key, use our Authorize API or go to our API Explorer on this site to generate your access token. You can use this token and the other Sandbox credentials to try any of our APIs.

1. In the BMO Developer Portal, select your username and choose My Apps from the dropdown.
2. Select the Register New App button.
3. Fill in the details and select Register New App.

Once you have your key, go to our sandbox and generate an Access Token. You can use this token to test any of your registered apps.

Your API key is one of the credentials we assign to you. It lets us verify your identity and determine which application is trying to connect to our APIs.

In our Sandbox, the API key can be shared for all your applications and can be found under “My applications” along with other credentials. Here, we also offer 2 distinct API keys that will determine the language you want to receive your code responses in.

For our Pre-Production and Production environments, we'll send you a separate, unique API key for each application.

All our APIs use the standard OAuth 2.0 framework.

To get authorized to make calls, please check our Authorize documentation. It contains all the information you’ll need to implement a two-legged or three-legged OAuth flow.

You need to generate and use an access token to authorize your application to connect to our Sandbox, Pre-Production or Production environments. You can generate Sandbox access tokens in our API Explorer tool on this site or use the Authorize API. For Pre-Production and Production environments, you need to generate your access tokens using our Authorize API only. For more details, please view our Authorize API documentation

The credentials you use depend on whether you're connecting to our Sandbox, Pre-Production or Production environment.

In our Sandbox and Pre-Production environments, all sign-in credentials are pre-filled for you.

When you're ready to launch your application and grant access to your accounts, please use your existing Online Banking for Business credentials.

When you make a GET call to our system, specifically Search for Accounts, you'll be returned a list of authorized accounts. For security reasons, these accounts will be identified with a unique account ID that is different from the account number.

To see which account is associated with the account ID returned, check the account_number field in the body of the return.

When you connect an application in production, you’ll be able to see the same accounts you’re entitled to in Online Banking for Business.

As part of the authorization flow, you’ll be able to choose which accounts you’d like to grant access to.

Apart from the Authorize API to give your application secure access to our servers, you’ll only need the Image Retrieval API to retrieve deposit images.

Once your application has been authenticated using the Authorize API, you can start your search for deposit images. Here's how it works:

• Get a list of your authorized Online Banking for Business accounts.
• Specify the account number, date range and item type. You can also add other search criteria.
• From the index of available images, choose the ones you want to retrieve.

The process is the same for Canadian and U.S. items.

You can request images of deposited items as far back as 7 years. To retain them even longer, you can use the API to automatically download and store them in your own archive.

Apart from the Account Validation API to verify account ownership, you’ll also need the Authorize API to give your account secure access to our servers and the Encryption API to protect sensitive information from end-to-end.

Currently, this API only supports U.S. savings and deposit accounts.

Each call can validate up to 100 accounts. There’s no limit for the calls you submit.

You can choose if you want to check account ownership, risk level or both. Simply submit the details you want us to check.