Clearing customs should be straightforward. But for thousands of importers every year, shipments get held, delayed, or penalized — not because of the goods themselves, but because of avoidable mistakes in paperwork, classification, or compliance.
Whether you’re a seasoned importer or shipping into Canada for the first time, these errors can cost you time, money, and client relationships. Here are the 10 most common customs mistakes — and exactly how to avoid them.
Mistake #1 — Incorrect Tariff Classification (HS Code)
Every product imported into Canada must be assigned a Harmonized System (HS) code — a globally standardized number that determines the duty rate applied to your goods.
What goes wrong:
- Wrong HS code = wrong duty rate
- Can trigger CBSA flags and full inspections
- May result in penalties or back-payment of duties
How to avoid it: Work with a licensed customs broker who specializes in tariff classification. A single digit wrong can cost thousands.
Mistake #2 — Incomplete or Inaccurate Commercial Invoice
The commercial invoice is the single most important document in a customs entry. CBSA uses it to assess the value, origin, and nature of your goods.
Common errors:
- Missing buyer/seller details
- Incorrect or vague product descriptions
- Wrong currency or unit of measure
- Missing country of origin
How to avoid it: Use a standardized invoice template and have your customs broker review it before shipment departs.
Mistake #3 — Undervaluing Goods
Some importers deliberately — or accidentally — declare a lower value to reduce duty payments. CBSA is trained to catch this.
What happens:
- Shipment gets flagged for a detailed examination
- Duties reassessed at full value plus interest
- Potential penalties and import bans in serious cases
How to avoid it: Always declare the true transaction value including any assists, royalties, or additional costs paid to the seller.
Mistake #4 — Missing or Incorrect Country of Origin
Country of origin determines whether your goods qualify for preferential duty rates under trade agreements like CUSMA (Canada-US-Mexico Agreement) or other FTAs.
What goes wrong:
- Claiming CUSMA preference without a valid Certificate of Origin
- Listing country of manufacture incorrectly
- Missing origin marking on goods or packaging
How to avoid it: Confirm origin documentation with your supplier before shipment. Your customs broker can verify eligibility for duty relief.
Mistake #5 — Not Having the Right Permits or Licences
Certain goods entering Canada require permits, licences, or certificates from specific government agencies before they can be released.
Examples:
| Product Type | Required By |
|---|---|
| Food & Agriculture | CFIA |
| Firearms & Weapons | RCMP / Public Safety Canada |
| Health Products | Health Canada |
| Textiles & Apparel | Global Affairs Canada |
| Endangered Species | Environment Canada (CITES) |
How to avoid it: Research permit requirements before your goods ship. Last-minute permit applications cause serious delays.
Mistake #6 — Poor Communication Between Freight Forwarder and Customs Broker
Your freight forwarder and customs broker need to be in sync. When they aren’t, critical documents arrive late, entries get filed incorrectly, or cargo misses release windows.
What goes wrong:
- Arrival notices not forwarded in time
- Missing documents at time of customs filing
- Delays in cargo release due to miscommunication
How to avoid it: Establish a clear communication chain. Ideally, introduce your customs broker to your freight forwarder so both parties coordinate directly.
Mistake #7 — Filing Customs Entry Too Late
CBSA requires customs entries to be filed within specific timeframes depending on mode of transport. Missing these windows leads to storage fees, demurrage charges, and inspection holds.
Deadlines by mode:
| Mode | Entry Filing Deadline |
|---|---|
| Air | Before aircraft arrival |
| Ocean | 24 hours before vessel arrival |
| Highway (truck) | At time of arrival |
| Rail | 2 hours before arrival |
How to avoid it: Send all shipment documentation to your customs broker as soon as goods are ready to ship — not after they’ve already departed.
Mistake #8 — Ignoring CBSA’s CARM Portal Requirements
The CARM (CBSA Assessment and Revenue Management) portal is now mandatory for all importers trading into Canada. Businesses that haven’t registered or set up their RPP Bond face serious clearance issues.
What goes wrong:
- Inability to self-release goods
- Delays caused by missing importer registration
- Loss of ability to pay duties directly
How to avoid it: Register on the CARM portal immediately if you haven’t already. Your customs broker can guide you through the setup and RPP Bond application process.
Mistake #9 — Mislabelling or Improper Packaging
CBSA officers physically inspect shipments that appear inconsistent with their declared contents. Improper or misleading labelling is one of the fastest ways to trigger a full examination.
Common issues:
- Labels not in English or French
- Packaging that doesn’t match product description
- Missing weight, quantity, or measurement markings
- Hazardous materials not properly identified
How to avoid it: Follow Canadian labelling standards and ensure packaging accurately reflects what’s inside — every time.
Mistake #10 — Assuming Last Shipment = This Shipment
Many importers assume that because a previous shipment cleared without issues, the next one will too. Regulations change. Products change. Trade agreements shift.
What changes without warning:
- Duty rates and tariff classifications
- Permit and licence requirements
- CBSA enforcement priorities
- Trade agreement eligibility rules
How to avoid it: Stay current with Canadian trade regulations or work with a customs broker who monitors changes on your behalf and flags anything that affects your specific goods.
Summary — Quick Reference
| # | Mistake | Risk Level |
|---|---|---|
| 1 | Wrong HS Code | 🔴 High |
| 2 | Incomplete Commercial Invoice | 🔴 High |
| 3 | Undervaluing Goods | 🔴 High |
| 4 | Wrong Country of Origin | 🟠 Medium-High |
| 5 | Missing Permits or Licences | 🔴 High |
| 6 | Poor Broker-Forwarder Communication | 🟠 Medium |
| 7 | Late Customs Entry Filing | 🟠 Medium-High |
| 8 | Not Registered on CARM | 🔴 High |
| 9 | Mislabelling or Wrong Packaging | 🟡 Medium |
| 10 | Assuming Rules Haven’t Changed | 🟠 Medium-High |
Final Word
Most customs delays are not caused by the goods — they are caused by gaps in documentation, classification errors, and poor preparation. The good news is that every single mistake on this list is preventable.
Working with a licensed customs broker means having an expert in your corner who catches these issues before your shipment reaches the border — not after it’s already been held.
Avoid costly delays. Contact Great North Customs Brokers today and let us handle your customs clearance — accurately, efficiently, and on time.