If there’s one thing that catches businesses out time and time again, it’s customs paperwork.
Many companies have been importing goods for years without any real issues, so why change? The challenge is that customs requirements continue to evolve, and small errors that might not have been a problem in the past and that you could easily slip through can now lead to delays, additional costs, or unwanted attention from customs authorities.
We regularly speak with businesses that come to us after managing their own freight and were surprised to discover that a shipment has been held up because of something that seemed relatively minor. Often, it’s not a complicated compliance issue. It’s a simple mistake that has been repeated for months or even years without anyone noticing.
Here are some of the most common customs mistakes UK importers still make and what can be done to avoid them.
Using Vague Product Descriptions
This is a common mistake and understandable because less detail was required in the past than it is now.
Businesses often use generic descriptions such as:
- Machine parts
- Components
- Samples
- Accessories
- Equipment
The problem is that these descriptions do not tell customs authorities much about what is actually being imported.
A shipment described as “machine parts” could contain thousands of different products. Customs systems increasingly expect more specific information to help identify goods accurately and assess any potential risks.
A better description might be:
- Stainless steel bearings for industrial machinery
- Plastic automotive dashboard clips
- Electronic control units for manufacturing equipment
It takes a little more effort, but it can make customs clearance far smoother.
Incorrect Commodity Codes
Commodity codes play a major role in international trade. They help determine duties, taxes, restrictions, and customs requirements.
Unfortunately, many businesses either:
- Use outdated codes
- Copy codes from previous shipments without checking them
- Rely on suppliers who may have classified goods incorrectly
We’ve seen cases where a code has been used for years simply because “that’s what we’ve always done.”
The trouble is that using the wrong commodity code can lead to:
- The wrong duty payments
- Further customs queries
- Delays during clearance
- Potential penalties if errors are discovered later
It’s worth reviewing commodity codes periodically, particularly if products change or suppliers introduce new variations.
Inconsistent Information Across Documents
Another common problem is inconsistency, particularly when the commercial invoice does not match the packing list.
Likewise, when the customs declaration contains different quantities or descriptions, it can be a problem.
Individually, these differences may seem insignificant, but together, they can create confusion during customs checks, and given that modern customs systems are increasingly data-driven, these discrepancies are more easily picked up.
When information does not match, customs authorities may request clarification before allowing goods to proceed.
That can add days to a shipment that was otherwise moving perfectly well.
Assuming Someone Else Is Handling Compliance
Many importers assume that because they use a freight forwarder, courier, or customs broker, all compliance responsibilities automatically transfer to that provider.
In reality, customs agents can only work with the information they’re given, and if incorrect information is supplied at the start of the process, it often gets carried through the supply chain.
A good freight partner, though, will identify obvious issues where possible, but ultimately, importers remain responsible for the accuracy of the information being submitted.
It’s always worth understanding what data is being declared in your name.
We often see these issues arise during a company’s first few international shipments, when customs processes and responsibilities are still unfamiliar. That’s something we explored in The First Shipment Problem: Why So Many Businesses Get Caught Out Early.
Failing to Review Supplier Documentation
A lot of businesses place significant trust in overseas suppliers. Most of the time, that’s perfectly reasonable.
However, supplier paperwork is not always accurate, and we’ve seen invoices containing:
- Incorrect product descriptions
- Missing values
- Wrong country of origin information
- Outdated company details
These issues can create unnecessary customs complications once goods arrive in the UK, so taking a few minutes to review documentation before shipment can save a lot of time later.
Ignoring Changes to Customs Requirements
Customs authorities seem to be continually trying out and introducing new IT systems, reporting requirements, and security measures.
Many companies understandably focus on running their business and are inclined to only really worry about customs when a problem appears.
A proactive approach where customs requirements are provided at the start, though, is a much better and effective way to work, and you will likely find a much less stressful way moving forward.
A good example is ICS2, the EU’s Import Control System 2, which is changing how shipment information is submitted before goods enter Europe. We covered this in more detail in our recent guide on, What is ICS 2.
Keeping up-to-date on the latest customs developments can help you avoid unexpected disruption, and one of the easiest ways to do this is to use a freight forwarder such as RSJ International.
Treating Customs as an Administrative Task
Some businesses still view customs paperwork as little more than administration, while the reality is that customs compliance has become an increasingly important part of international supply chains.
Poor documentation can lead to:
- Delayed deliveries
- Additional storage charges
- Missed customer deadlines
- Increased costs
- Damaged supplier relationships
Good customs processes do not just keep authorities happy. They help keep freight moving efficiently.
Getting the Basics Right
As a business, very often this is about simply paying careful and close attention to product descriptions, commodity codes, and any additional documentation that you can include.
The companies that experience the fewest customs problems tend to be the ones that take seriously having a clear process and a habit of checking details before goods leave the supplier.
Businesses that stay organised and work closely with experienced freight and customs partners are generally in a much stronger position to avoid unnecessary delays and costs.
If you’re unsure whether your current import procedures could be improved, it’s worth having a conversation before problems arise rather than after a shipment has already been held at customs.
If you’re new to importing, our article 21 Questions Businesses Often Ask Freight Forwarders also covers many of the practical questions businesses have when shipping internationally.
For advice on customs procedures, freight forwarding, and international shipping, contact RSJ International’s team here: https://rsj-international.co.uk/contact-us/
You can also read our recent article on ICS2 and how it may affect freight shipments into Europe in 2026.
