Why does the IRmark on a tax return change?

Article ID: 1304
Last updated: 04 Jun, 2024

What is the IR Mark?

The IR Mark is a software generated reference and assists in the creation of the File By Internet Receipt returned by HMRC. It is a mechanism which could potentially be used during investigations, to aid taxpayers and HMRC in ensuring that the submission sent and received match each other.

The IR Mark is unique and is generated using the Tax Return entries and attachments.

When and where does the IR Mark get created in TaxCalc?

In TaxCalc the IR Mark is generated when the tax return is created for viewing as a pdf or printing, using the client/HMRC options in Filing Preferences. It will also be generated without viewing or printing when choosing ‘File tax return online to HMRC’ (filing screen). Once created, the IR Mark will be seen under the client name within the filing screen. It will also be seen at the top of every page of the ‘printed’ tax return, alongside the unique tax reference (UTR). Once the return is filed, it is also stored in the submission log which can be viewed by clicking on the ‘Full details’ button within the filing screen.

When and where could the IR Mark change?

The IR Mark within the tax return pages will change if:

In these circumstances, locking the return will avoid inadvertent changes which will prevent any potential change to the IR Mark. This can be done from the top menu in File > Lock return.

The IR Mark may also change after a software update. A software update should only result in a change if:

  • there have been changes in the calculations or forms layout (schema) after implementation of an HMRC update
  • there have been changes in the calculations to resolve an issue or enhance functionality
  • changes have been made to attachments that are generated by the system

For a submitted return, the IR Mark on the filing screen and within the submission receipt do not change, regardless of any of the changes above.

What can be done to mitigate a change in the IR Mark within the return pages?

Unfortunately, based on how the IR mark is generated, it’s not possible to prevent the IR mark changing if the software update necessitates it. If, however, the return has not been filed but a copy has been sent for approval, you could take one of the following steps:

  1. Where possible, avoid updating the software until the returns have been approved and submitted.
  2. If an update cannot be avoided and the IR Mark changes, you could send another return for approval.
  3. Make a note of the Tax Returns that were with clients at the time of the update, so you are aware that the software update could have affected those returns.

Once the return is filed:

  1. Save a copy of the return (virtual or hard copy) at the time of approval and submission. This can be done from within the filing screen by clicking ‘Print’ and we would advise to tick ‘Do you want to include HMRC’s online filing response?’
  2. Save a copy of the submission receipt with the tax return. This can be saved by clicking on ‘Full details’ from within the filing screen.

The submission receipt contains the IR Mark at the time of submission, along with all the entries from the return that have been submitted to HMRC. It is created in xml so in order to view in a user friendly format, we suggest right-clicking on the file in Windows Explorer (or equivalent) and choosing ‘Edit with Notepad ++.

Article ID: 1304
Last updated: 04 Jun, 2024
Revision: 9
Views: 7005
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