Release notes (13 May 2020)

What’s New?

We’ve pushed a new release of the UK Trade Tariff with the following features:

  • PDF downloads of the whole tariff and chapter by chapter (in beta)
  • Chemical search by name or CAS number

What is a CAS number?

A CAS Registry Number, also referred to as CASRN or CAS Number is a unique numerical identifier assigned to every chemical substance described in the open scientific literature.

More information about CAS may be found at


The chemical search feature is also exposed through the V2 API. Documentation for the new endpoints has been added here:

API Examples

  • GET /chemicals/{cas} - Retreives a chemical by its CAS number

$ curl -X GET

We would appreciate any feedback on both of these new features!


Hi @matt_bitzesty appreciate the new changes made :ok_hand:. Could you please explain the benefits of the PDF. Is the objective of the PDF to be updated with the latest changes when they’re made to the UK tariff? If not how frequently will it be updated as I see already certain differences from its first published date and today’s data.

Thank you!

Hi @praveenkumar

The pdf tariff should be in sync with the online tariff, so if you spot any differences please let me know!

It’s updated daily and acts as an offline backup of the online tariff.


Hi @matt_bitzesty,
Thanks for your reply.

  1. Here’s what UK Trade Tariff currently displays:
    and here is what the PDF displays: . The blue lines show where the missing numbers should appear.
  2. I see the PDF is last updated on 24th April 2020. It would be great to have the latest PDF for reference.
  3. Could you please retain the headings of every column in all the pages to make it more reader-friendly?
  4. An RSS Feed option would be a nice feature to have so that people who subscribe to it get notified when a new PDF version is available.

Looking forward to your comments.


Hi Praveen,

Thanks, it looks like out production server is picking up an old version of the tariff, it might be due to caching, we’ll investigate and resolve that as soon as possible.


@praveenkumar thanks for the feedback - we’ve updated the PDF document

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Hey @matt_bitzesty,
Just verified it and looks good. So can expect this now to be updated daily or as and UK Tariff undergoes changes?


Hi @praveenkumar,

The PDF is regenerated each morning to capture the changes for the next day. It could be slightly out of date by a day depending on when the changes take effect, or if the generation process fails.

We’re monitoring this and it should be stable going forward, but we’re still in beta for this feature and welcome feedback.


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The HMRC endpoint is great if you have a CAS number that is listed in the schedules – e.g something very common, but the vast majority of most chemicals won’t have a CAS number in the schedules and you need to manually work out the correct code from the structure. But there is a commercial solution that can do this for you.

You can either search for the chemical by name, or even better, draw it in, upload a smiles / inchi string or .mol file with the chemical structure.

As it accepts chemical structures you can use if for almost any organic chemical, including novel and proprietary ones. Some details on it are at

Hope someone find that useful


Hi @jbradl,

The CAS search endpoint should also include chemicals that are listed in the HMRC correlation tables

These link chemicals to which do not have a CAS number in their description, so you can still search for them. You do need to however know the CAS number.