Merchants are experiencing discrepancies between Shopify’s built-in duties and tax calculator and actual DDP (Delivered Duty Paid) charges from carriers for US-to-Canada shipments. The core issue: Shopify’s tool is only an estimator, yet it charges customers for duties and taxes that don’t match what carriers (DHL, FedEx, UPS, USPS) actually bill. This results in unexpected back charges on both DDP and non-DDP shipments.
Shopify’s Position:
Support confirms the calculator is an estimator and cannot guarantee accuracy
No commitment to improving calculation precision
Suggested Workarounds:
Verify HS codes and product origin directly with customs brokers/carriers
Use carrier-specific landed cost calculators (DHL Duty & Tax, FedEx My Global Trade Manager)
Consider third-party apps like Zonos, Avalara, or Easyship for accurate DDP calculations
Document discrepancies and work with carrier account reps for adjustments
Merchant Concerns:
Third-party solutions are prohibitively expensive for smaller businesses
Fundamental question remains: why charge customers if it’s just an estimate?
Multiple merchants confirm this is a widespread, ongoing problem
Status: Unresolved—no native Shopify solution available; merchants must choose between accepting inaccuracy or paying for external tools.
Summarized with AI on October 25.
AI used: claude-sonnet-4-5-20250929.
We’re having an issue where the Shopify-built-in duties and tax calculator is not calculating correctly according to what we’re being charged for our DDP labels. We’re a US-based company, and these are shipments going to Canada, and it seems they’re being charged some of the tariffs right now. We’ve gone through everything, from checking HS codes and ensuring settings are correct to quoting with all the carriers, i.e., DHL, FedEx, USPS, UPS. Is anyone else having these issues? We’ve talked with Shopify Support, and they basically said our calculator is just an estimator, so we can’t guarantee its accuracy. We’ve also talked with all the shipping providers, and nobody seems to understand or know what’s going on or how to handle this.
We’re also concerned as we’re getting bills from non-DDP shipments for these tariffs as a back charge, as it seems the shipping companies and just now starting to understand how to quote and charge for this. We cannot be the only ones running into this!
Shopify’s duty calculator is only an estimate and won’t include carrier specific add-on’s You may consider partnering a duty landed cost tool such as Zonos or Avalara that has been developed to accurately assess duty taxes based on HS codes and carrier regulations This will ensure that you are charging according to actual DDP invoices and ultimately cutting down on unforseen back charges. Hope this helps.
Yes, I know that’s the same thing Shopify said, but why would they offer it and charge our customers for the duties and taxes if it’s just an estimator? You would think they would be more on top of it and get their calculator correct. If it’s just an estimator, they should just estimate taxes and not actually charge them. Zonos and Avalara are disgustingly expensive for a company like us, so that’s not a realistic solution either.
Hi there,
You’re definitely not alone — a lot of merchants have run into the same issue with Shopify’s built-in duties and tax calculator. The important thing to note is that Shopify’s tool is more of an estimator, and it doesn’t always align perfectly with how carriers (DHL, UPS, FedEx, etc.) apply tariffs, surcharges, or DDP billing in practice. That’s why you’re seeing discrepancies and even back charges on non-DDP shipments.
A couple of things you can consider:
Confirm HS codes & product origin with your customs broker/carrier directly, since Shopify doesn’t control how customs authorities classify and bill shipments.
Use carrier-provided landed cost calculators (e.g., DHL Duty & Tax, FedEx My Global Trade Manager) — these tend to be closer to what you’ll actually be billed.
If accuracy is critical, you might want to look at third-party landed cost apps (Zonos, EasyShip, etc.) that specialize in DDP/DDU calculations and sometimes integrate directly with Shopify.
Keep documentation of your charges and share them with your carrier’s account rep — they can sometimes adjust misapplied tariffs.
In short: Shopify’s tool is helpful for giving customers a rough idea, but if you need guaranteed accuracy for DDP billing, you’ll want to rely on carrier tools or a specialized duty/tax solution.
It sounds like you’re running into a common issue with Shopify’s built-in duties and tax calculator. Unfortunately, as Shopify Support mentioned, the calculator is just an estimator, so it can’t guarantee 100% accuracy. This often leads to discrepancies when calculating DDP duties and taxes, especially with international shipments like those to Canada.
To address this, here are a few things you could try:
Check Your Settings: Double-check that the “Customs Duties” and “Tax” settings are configured correctly in your Shopify admin, and ensure that your products are categorized with the right HS codes and product descriptions.
Consider a Third-Party App: If Shopify’s built-in calculator isn’t providing accurate results, you might want to look into third-party apps like Zonos or Easyship. These apps can handle more precise duties and tax calculations and offer better integration with international shipping.
Work with Your Carriers: Since you’re dealing with international shipping, it’s important to have open communication with your carriers. Consider discussing your exact requirements with them and ask for specific details about how they handle DDP charges and tariffs.
As for the back charges on non-DDP shipments, it’s an issue that’s becoming more prevalent as shipping providers adapt to DDP and international shipping requirements. If this continues to be a recurring issue, it might be worth considering switching to a more specialized solution that can integrate directly with Shopify and your carriers for accurate billing.
You’re definitely not alone—many merchants face similar issues when shipping internationally. Hopefully, these suggestions will help get things sorted. Let me know if you need further guidance!
I am also running into this problem. Shopify is charging the customer for duties. If this is just an estimator, why is shopify charging the customer for it? Zonos for Shopify is crazy expensive too.