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Pay CBAM on real emissions, not defaults.
We collect verified emissions from your suppliers and prepare your return and audit pack. You or your customs agent submit it to HMRC.
UK CBAM applies from 1 January 2027
We manage your suppliers
Requests go out in each supplier’s language, under your name. We chase every 7 days.
Default values can’t be swapped out after you file.
File your 2027 return on default values and you can’t amend it later to use your suppliers’ verified figures. Supplier data has to be in before the return is due on 31 May 2028.
8 (1)A person who has made a return under paragraph 7 may amend the return by notice to HMRC (and may further amend the return by further notice to HMRC) only in order to correct an error.(2)No amendment may be made to replace information on the emissions embodied in CBAM goods determined using default values set under paragraph 11 with such information determined in accordance with regulations under paragraph 10.
Your liability, quarter by quarter
It updates as each supplier responds.
Suppliers submit once, for every UK buyer
Your overseas suppliers use Oportax free.
Your return, ready to submit
Oportax prepares your return and audit pack. You or your customs agent submit it to HMRC.
Built for UK CBAM from the start.
Start collecting supplier data now
In 30 minutes we’ll go through your imports, your suppliers and what Oportax takes off your desk.
Common questions
When should I start?
Now: supplier data takes months to collect, and your 2027 return needs it by 31 May 2028.
How does Oportax lower what I pay?
Your saving is tonnage × the gap between your suppliers’ emissions and the default × the CBAM rate.
Do you submit returns directly to HMRC?
No. We prepare your return and audit pack. You or your customs agent submit it to HMRC.
Where is my data stored?
Customer data is encrypted at rest with AES-256 and in transit with TLS.