Proof of Origin after Brexit – EUR.1 vs REX vs Statement on Origin [when to use which]

Since Brexit, trade between the European Union and the United Kingdom has been governed by the Trade and Cooperation Agreement (TCA) — and it is this agreement that determines whether your goods will attract customs duty at the border or not. The good news: most goods qualifying as "originating in the EU" or "originating in the UK" can benefit from a preferential duty rate of 0%. The bad news: the TCA provision alone is not enough — you must prove that origin with the correct document. This is where confusion sets in, because there are three different types of proof: EUR.1, REX, and statement on origin. Each has different requirements, different applications, and different consequences if something goes wrong. This article explains exactly when to use each document, who may issue it, how to register in the REX system, and what happens when a customs officer finds an error in your proof of origin. You will also find information on cumulation rules, which are often overlooked yet can determine whether your product qualifies for 0% duty at all.

Why proof of origin is critical after Brexit

Before Brexit, goods moved freely between the UK and the EU without duties and without any need to prove where they came from. From 1 January 2021 everything changed. The TCA introduces a 0% duty rate — but only for goods that meet the Rules of Origin. Without a valid proof of origin, the customs officer will assess full MFN (Most Favoured Nation) duty, which depending on the product can range from a few to several dozen per cent.

The rules on proof of origin are published on gov.uk.

The key question is: does your product actually qualify as "originating in the EU" or "originating in the UK"? The answer is not always obvious. The TCA contains detailed rules — for example, a requirement for "sufficient processing" or the satisfaction of added-value criteria. Only once a product qualifies for the preference do you choose the appropriate type of proof.

Comparison of the three types of proof of origin

The table below provides a quick overview of the differences:

Feature	EUR.1	REX	Statement on origin
Who issues it	Customs authority	Registered exporter (self-certification)	Any exporter (up to EUR 6,000) or REX exporter
Value limit	None	None	Up to EUR 6,000 (without REX)
Validity	10 months	Indefinite (per export)	12 months
Time to obtain	1–3 working days	One-off registration (~7 days)	Immediate
Cost	Official fee	Free registration	None
Use case	One-off exports or when REX is not held	Regular exports of any value	Small consignments or REX exporters

EUR.1 – when and how to obtain a movement certificate

EUR.1 (Movement Certificate EUR.1) is the traditional document issued by the customs authority of the exporting country. In Poland it is issued by the Customs and Fiscal Office (Urząd Celno-Skarbowy) responsible for the exporter's place of business.

When to use EUR.1: - When the exporter is not registered in the REX system - For one-off or occasional exports - When the value exceeds EUR 6,000 and the exporter does not hold REX status - When the UK importer requires a "hard" document bearing the customs office stamp

How to obtain EUR.1 in Poland: 1. Complete the EUR.1 form (available at the customs office) 2. Submit the application to the Customs and Fiscal Office together with the commercial invoice and documents evidencing origin (e.g. supplier declarations, materials invoices) 3. The office verifies that the goods genuinely satisfy the TCA Rules of Origin 4. The certificate is issued and stamped

Important: the EUR.1 issued after Brexit for exports to the UK is not the same as the old EUR.1 used for other AEO countries. Ensure the form is correct for the UK–EU TCA.

Risk: if you export regularly and visit the customs office every time, you are wasting time and money. For regular exporters REX is a far better solution.

REX – Registered Exporter System: how it works and how to register

REX is the registered exporter system that allows you to declare the origin of goods yourself, without involving the customs authority. It is designed for companies that export regularly to the UK and want to save time and money.

How REX works: - The exporter registers once in the REX database - Once a REX number is obtained, the exporter can self-certify origin declarations on commercial invoices or other commercial documents - There is no consignment value limit - A REX exporter may also issue a statement on origin for consignments above EUR 6,000

How to register as a REX exporter in Poland: 1. Submit an application electronically via the PUESC portal (portal.puesc.gov.pl) 2. Attach company registration documents and a declaration confirming knowledge of the Rules of Origin 3. Processing time: usually 5–10 working days 4. You receive a REX number in the format: PL/REX/XXXX/XXXX 5. The number appears in the European Commission's public REX database

Obligations of a REX exporter: - The exporter is personally responsible for the accuracy of declarations - Supporting documentation confirming that the Rules of Origin are met must be retained for at least 4 years - Incorrect declarations may result in revocation of REX status and liability for unpaid duty

Statement on origin – for small consignments and REX exporters

A statement on origin is a declaration placed on a commercial invoice or other commercial document stating that the goods originate in the EU (or the UK). It is the simplest form of proof of origin.

When a statement on origin may be issued WITHOUT REX registration: - Only when the consignment value does not exceed EUR 6,000 - The declaration may be entered directly on the commercial invoice

When a REX exporter may issue a statement on origin: - For consignments of any value - On the invoice, waybill or another commercial document

Wording of a statement on origin in accordance with the TCA:

The exporter of the products covered by this document (Exporter Reference No. [REX number or "not applicable for consignments below EUR 6000"]) declares that, except where otherwise clearly indicated, these products are of [EU or UK] preferential origin.

[Place and date]
[Exporter's signature]

Note: the absence of a REX number on a consignment worth more than EUR 6,000 will invalidate the declaration and result in full duty being assessed by UK customs.

What UK customs checks when examining proof of origin

HMRC (His Majesty's Revenue and Customs) checks the following when inspecting proof of origin:

1. Formal document requirements — whether the EUR.1 bears the customs office stamp, whether the REX number is valid, whether the statement on origin contains all required elements
2. Consistency with the commercial invoice — the value, goods description, and quantity must agree
3. Rules of Origin — whether the HS code of the goods can qualify for TCA preferences at all and whether the declared origin is plausible
4. Expiry dates — EUR.1 is valid for 10 months from the date of issue

What happens if the proof of origin is incorrect: - The importer pays full MFN duty (no preference) - HMRC issues a demand for payment with interest on the duty that was not paid at the time - If fraud is suspected — a formal investigation is opened - The EU exporter may be notified by EU customs authorities of the need for post-clearance verification

Cumulation rules – when materials from another country "count" towards origin

Cumulation is a mechanism that allows materials or processing carried out in a partner country to be treated as one's own. In the context of the UK–EU TCA there is bilateral cumulation: materials "originating in the UK" used in EU production may be treated as EU materials, and vice versa.

Practical example: a furniture manufacturer in Poland uses metal components from the UK. When calculating whether an armchair meets the Rules of Origin for export to the UK, the UK components count towards the "EU/domestic" value. This can determine whether the product qualifies for the preference at all.

Key limitation: cumulation only applies where the final processing exceeds "minimal operations". Simple assembly of basic components is often insufficient.