Two HMRC documents describe the same exception differently, and a business importing ferro-silicon falls in the gap between them. The gap is narrow, it decides whether the tax applies at all to those consignments, and it is settled by reading the Act rather than either document.
What each source says
Schedule 16 to the Finance Act 2026 lists chapter 72, iron and steel, as covered, then prints a list of exceptions within it. Within the ferro-silicon subheadings that list names 7202 21, and it names no other. The remaining exceptions in chapter 72 are 7202 30, 7202 50, 7202 70, 7202 80, 7202 91, 7202 92, 7202 93, 7202 99 10, 7202 99 30, 7202 99 80 and 7204. The Act does not except 7202 29, so a good declared under that code sits inside the Table.
HMRC’s scope guidance agrees with the Act. The iron and steel page in “Check which goods are in scope of Carbon Border Adjustment Mechanism (CBAM)”, published on 16 July 2026, prints its exception as “Except 7202 21 within 72 Ferro-silicon”, and lists the same further exceptions as the Act.
The annex to HMRC’s policy summary does not agree. That document, published on 10 February 2026 and updated on 9 September 2026, prints “Except: 7202 2, Ferro-silicon”, where the comma stands for a long dash in the original. The subheading 7202 2 is wider than the code 7202 21, and reading the annex on its own takes every ferro-silicon code out of the tax, 7202 29 included.
Which one governs
The charge is imposed by the Act. Section 143 charges CBAM on the emissions embodied in a CBAM good, and section 143(2) and (3) define a CBAM good by reference to Schedule 16. A policy summary is guidance. It describes the tax and it does not impose or remove it, and where guidance and the Act part company the Act is what an officer and a tribunal will read.
That is not a criticism of the annex. It reads like a drafting shortcut, the sort of abbreviation that happens when a subheading is written at four digits and two rather than at its full length. What matters to an importer is that the shortcut is not the law, and that relying on it is a position taken against the text of the Act.
What an importer of ferro-silicon should do
Treat 7202 29 as a covered code until a correcting instrument or a revised annex says otherwise.
Count it towards the registration threshold. Paragraph 2 of Schedule 17 measures the threshold by the value of the CBAM goods imported, and if the goods are covered they count. A business whose ferro-silicon imports sit near 50,000 pounds over a rolling twelve months decides its registration date on the strength of this question.
Keep the records as though the tax applies. If the position later changes in the importer’s favour, the way back is paragraph 25 of Schedule 17, which allows a claim for an amount that was not tax due. The claim is limited to amounts paid within the three years before it is made, and HMRC may resist it where repayment would unjustly enrich the claimant, which is the ordinary position where the tax was passed on in the price. A claim needs the same evidence the return needed, so the records have to exist either way.
Ask the supplier for emissions data now. An installation that has never been asked for a verified emissions intensity takes months to produce one, and the alternative is the default value, which paragraph 11 of Schedule 17 allows the Treasury to set so that no advantage arises from using it.
The narrower question underneath
Whether a particular consignment is 7202 21 or 7202 29 is a classification question about the goods, and it is answered from the tariff and the declaration rather than from this site. The commodity code checker reads the code as typed and applies the Table in Schedule 16 to it; it returns the warning above for 7202 29 and treats 7202 21 as excepted. Where a business has been declaring ferro-silicon under a residual code out of habit, the classification is worth settling before January, because the code on the declaration is what decides the tax and the same code decides the threshold.
If HMRC issues a correcting instrument, or revises the annex to match the Act, the change will appear on the updates page with the date it was read.
What this affects
Chapters 1, 28 of UK CBAM for Importers covers the same ground in full.