Simplifying customs declarations for UK ecommerce exports

Customs declarations are mandatory for most goods exported from the UK to countries outside the UK, including the EU. Understanding the required forms, accurate commodity codes and available software helps small ecommerce brands avoid delays, extra costs and compliance issues.

This guide outlines the practical steps UK early-stage founders and ecommerce sellers need to take when preparing shipments, focusing on what actually matters for day-to-day operations.

When do you need a customs declaration?

Any commercial shipment leaving the UK for a destination outside the UK generally requires a customs declaration. This includes sales to customers in the EU, the United States, Australia and most other markets. Gifts and very low-value items may have simplified rules, but these change and must be checked on GOV.UK for each destination.

Sellers using fulfilment centres abroad or shipping directly from the UK need to ensure declarations are completed before the parcel reaches the carrier. Missing or incorrect declarations can result in the parcel being held at the border, returned or subject to additional handling.

Required forms and documents for export

The main document is the export declaration, submitted electronically through the Customs Declaration Service or compatible software. For many small parcels this is combined with the commercial invoice that accompanies the physical shipment.

Commercial invoice: Must include seller and buyer details, description of goods, quantity, value, commodity code, country of origin and reason for export. A separate invoice is needed for each international parcel.
Export declaration: Electronic submission that provides data to HMRC. For low-value or low-volume shipments some carriers offer simplified options through their own platforms.
Proof of export: Retained records showing the goods left the UK, useful for VAT purposes. Check current GOV.UK guidance as requirements vary.

Carriers such as Royal Mail, DPD, UPS and DHL often integrate declaration tools into their shipping labels, reducing the need for separate paperwork in many cases.

Understanding and using commodity codes

Commodity codes, also known as HS codes or tariff codes, are numerical classifications that identify the type of goods being shipped. The UK uses an 8- or 10-digit system depending on the destination. The first six digits are usually harmonised internationally, with additional digits added for UK or destination country requirements.

To find the correct code, start with the GOV.UK Trade Tariff tool. Search by product description or browse chapters relevant to your goods. For example, a cotton t-shirt might fall under chapter 61 for clothing, with a more specific code based on material, gender and style. Incorrect codes can lead to miscalculated duties or delays, so verify each new product type.

Practical tip: Create a spreadsheet listing your best-selling SKUs with their commodity codes, origin country and typical value. Update it whenever you add new products. Many software tools allow you to store these codes for reuse on future shipments.

Software that simplifies the declaration process

Several platforms reduce the manual effort involved in preparing customs data. Integrated carrier software from Royal Mail Click & Drop, DHL Express EasyShip or UPS WorldShip can generate both labels and declarations from order information. These systems pull product details from your ecommerce store and apply saved commodity codes.

Specialist customs software such as Avalara, ShipStation, or TradeTrust provide more advanced features including bulk declaration filing, automated commodity code suggestions and integration with accounting systems. Some connect directly to the HMRC Customs Declaration Service API, allowing submissions without logging into the government portal each time.

For very small volumes, starting with a carrier’s own online portal is often sufficient. As order numbers grow, moving to a dedicated platform can save time on repetitive data entry and reduce errors. Always test a few shipments to confirm the software produces acceptable declarations for your target markets.

Step-by-step process for preparing an export shipment

Confirm the destination country rules using the GOV.UK export checker tool for that market.
Assign the correct commodity code to each item using the Trade Tariff lookup.
Prepare a commercial invoice in English, including all required fields. Many platforms generate this automatically.
Enter shipment data into your chosen software or carrier portal, attaching or embedding the commodity codes and invoice details.
Submit the electronic export declaration before the carrier collects the parcel.
Print any required labels, barcodes and accompanying documents to include with the physical shipment.
Keep digital copies of all declarations and invoices for your records.

Repeat this workflow for each order. Once familiar, the process for repeat products becomes routine because saved codes and templates speed up data entry.

Common pitfalls and how to avoid them

Using vague product descriptions such as “clothing” or “gifts” often triggers customs queries. Be specific: “men’s cotton polo shirt, short sleeve” is far more useful. Similarly, under- or over-valuing goods can cause problems; use the actual selling price or cost price as appropriate and keep supporting records.

Another frequent issue is incorrect country of origin. For many UK sellers this is the United Kingdom unless goods were manufactured elsewhere. Check supplier documentation for imported items that are simply re-sold.

Finally, failing to update processes when rules change leads to rejected declarations. Set a reminder to review GOV.UK guidance every three months or when launching into a new country. Carrier support teams can also highlight frequent rejection reasons for your product types.

Building an efficient long-term system

Once the basics are in place, focus on efficiency. Integrate your ecommerce platform with shipping and customs software so order data flows automatically. Maintain a master product file with accurate weights, dimensions, commodity codes and HS descriptions. This file becomes the single source of truth for all export shipments.

Consider working with a fulfilment partner that handles international declarations on your behalf if volumes justify the service. For independent operation, choose software that scales with your business and offers good reporting on successful and rejected declarations.

Founders based at Loomworks or similar incubators often share practical tips on these systems with fellow ecommerce sellers in the space.

Frequently asked questions

Do I need a customs declaration for every order sent outside the UK?

Most commercial goods exported from the UK require an electronic customs declaration. Very low value items or certain gift shipments may qualify for simplified treatment, but rules vary by destination and change over time. Always check current GOV.UK guidance for the specific country and product type before shipping.

What is the best way to find the right commodity code?

Use the free GOV.UK Trade Tariff tool to search by product description. Start broad and narrow down until you reach the most specific code. Save codes for each product in a spreadsheet or within your shipping software to avoid repeating the lookup for every order.

Can carrier software handle the entire customs process?

Many carriers provide tools that combine label generation with basic customs declarations. For straightforward shipments this is often enough. More complex or high-volume needs may benefit from specialist software that connects directly to HMRC systems and offers better error checking.

How do I create a commercial invoice for exports?

Include seller and buyer addresses, a clear description of the goods, quantity, unit value, total value, commodity code, country of origin and the reason for export. Most shipping platforms can generate a compliant invoice from your order data automatically.

What records should I keep for UK export shipments?

Retain copies of commercial invoices, export declarations, proof that goods left the UK and any correspondence with carriers or customs. These records support VAT reclaim and compliance checks. Requirements can change, so refer to current HMRC guidance.