How to integrate Zonos via API to prepay U.S. duties and access shipping labels

If you're shipping packages from Canada to the United States using Canada Post, you must now prepay duties before your parcel crosses the border.

The recommended method to prepay U.S. duties is through automatic billing through a Zonos Verified Account:

For ecommerce merchants in our Developer Program – integrating Canada Post shipping services into their ecommerce website or platform – our Delivery Duties Paid (DDP) solution is currently available to Canada Post commercial customers who either:

  • Use a custom in-house shipping system integrated directly with Canada Post via our web services/APIs, or;
  • Ship with their own Canada Post account (BYOA) through a third-party platform that has integrated with Zonos.

Getting started with a Zonos Verified account for automatic billing

With a Verified Account you can:

  • Enable automatic billing from Zonos U.S. for duties and taxes
  • Enable Zonos to collect duties from your business and remit them directly to U.S. Customs and Border Protection (CBP) on your behalf
  • Access your U.S.-bound shipping labels in Snap Ship and Shipping manager immediately
  • Access Zonos’s classify tool to generate accurate HS codes and duty rates (so you can build duty into your shipping or product costs), or integrate with Zonos’s ecommerce apps to enable Zonos to manage that for you at checkout (at an additional cost).

How it works:

  1. You create a shipment as per your normal process
  2. Canada Post generates a Declaration ID
  3. Canada Post links the Declaration ID to your shipment's tracking number.
  4. Canada Post issues a shipping label (the Declaration ID confirms Zonos will collect and remit duties to CBP on your behalf).
  5. Using the tracking number and data shared from Canada Post, Zonos pays CBP directly for the shipment.
  6. Zonos invoices you for the duties associated with the tracking number.

How to set up a Verified Account

If you currently purchase U.S. shipping labels with an in-house custom development shipping system, you have the option to update your code of API call to Canada Post and sign up for a Verified Account with Zonos to obtain automatic billing.

What you need to do:

  1. Sign up for a Zonos Account
  2. Create a Verified Account
    • Click Create an account from the sign-up page.
    • You can sign up quickly with Google or Apple or enter your email address and Zonos will send you a 6-digit verification code. Enter this code to finalize set up.

    • Manual sign up – Enter your details:

      • Name
      • Email
      • Phone (optional)
      • Password
      • Accept the Terms of Service
    • Once complete, click Create Account to continue.
  3. Verify your email

    • To keep your account secure, Zonos will send a verification code to your email inbox.

      • Enter the code in the verification field.

    Didn’t get it? Click Resend to request another code.

  4. Add your business information

    • Enter your business details

      • Business name – The name of your company
      • Website URL – Your store or company website
      • Country – Where your business is base
      • Integration type – Choose the integration method that best fits your set up
    • Click Save when finished.
  5. Add a payment method
    • Keep a valid payment method on file so Zonos can invoice you directly for duties.
    • To connect a payment method:

      • Navigate to dashboard.zonos.com

      • Click on Settings
      • Select Billing
      • Click Add payment method
      • Enter your credit card details and click Save

      • Add the rest of your details:

        • Name
        • Email
        • Phone
        • Country
        • Address
      • Click Save to confirm your billing information.
      Reminder: Access to the Zonos Dashboard and its tools is free - no subscription fees. You’ll only be charged for duties (remitted to CBP by Zonos on your behalf) and the postal clearance/processing fee.
  6. Locate your Account Key
    • Once you have added a payment method and your account is approved, you'll receive a Zonos Account Key.
    • To locate your Zonos Account Key:

      • Navigate to dashboard.zonos.com

      • Click on Settings
      • Under Settings, you will see your Zonos Account Key.
  7. Add your Zonos Account Key

    If you’re using a custom in-house shipping system (via Canada Post web services/APIs):

    • Your developer must include the Zonos Account Key in the API header when making calls to Canada Post.
    • This enables Canada Post to generate and link a unique Declaration ID for each U.S-bound shipment.
    • Example header format: “X-CPC-Zonos-Key=xxxxxxxxxxx”
    • Estimated effort: Approximately 1.5 weeks (1 sprint with 2 developers and 1-2 QA resources)

    If you’re shipping with your own Canada Post account (BYOA) through a third-party platform integrated with our Zonos DDP solution:

    • Save your Zonos Account Key in your third-party platform settings.
  8. Create a shipment
    • Follow your existing process to generate a Canada Post US-bound shipping label
    • A Declaration ID is created and attached to your shipments tracking number. The declaration ID is your payment of duties validation – ensuring Canada Post knows duties are covered, so your label can be issued without delay
  9. Receive shipping label
    • Canada Post will issue the shipping label because the declaration ID confirms Zonos will connect and remit duties to CBP on your behalf.
  10. Proceed with Zonos Automatic Billing
    • The system automatically processes payments from your stored method.

How billing works with a Verified Account

  • Zonos collects duties for each shipment tied to your Verified Account.
  • You are invoiced directly by Zonos.
  • Zonos remits the duties to CBP on your behalf.

Duty calculation tools included with your Verified Account

Your Verified Account gives you access to Zonos Dashboard, which includes tools to help you calculate the duties on your products. With these calculations, you can build the true cost of cross-border shipping into your product or shipping price – so there are no surprises for you or your customers.

With your Verified Account, you can access the following tools:

  • AI-powered product classification
  • Real-time duty and tax calculators

By using these tools, you'll know precisely what duties will be charged on your packages. This transparency allows you to set accurate pricing, protect your margins and avoid surprise fees for your customers.

Tip: Zonos also offers a suite of ecommerce solutions that integrate directly at checkout. These solutions let you calculate and guarantee duties in real time for your shoppers – ensuring they see the full cost upfront, with no unexpected charges at delivery.

Tools and resources available to you:

  • Direct invoicing – All duty and tax charges are billed straight to you.
  • Full visibility – View a breakdown of duties per shipment in your Zonos Dashboard.
  • Useful reports – Download invoices, review payment history and export data for accounting.
  • Helpful tools – Access AI-powered product classification and real-time duty and tax calculators to know precisely what duties will be charged on your shipments.

Frequently asked questions