MTD 2025/26 known issues reported to HMRC
Users have reported the following issues with 2025/26 end of year filing and we have escalated where appropriate to HMRC as they may relate to data errors at their end.
The list is be read in conjunction with this article on end of year filing.
| Error | Description | untied comment |
| C55008 |
Period submission does not align to accounting period start date of 2025-04-06. Please amend and resubmit
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Reported to HMRC. If this relates to self-employment you could try changing your business settings |
| C55013 | Period submissions do not align to accounting period end date of 2026-04-05. Please amend and resubmit | Reported to HMRC. If this relates to self-employment you could try changing your business settings |
| C55107 | One or more employments have no directorship declaration submitted. Please submit. |
Users can fix this if it relates to a listed employment. We have updated the Employment section of our end of year filing article to explain what to do. Let us know if you still get this error We are also seeing this even if someone has no employments (or has pension income). In that case it needs to be escalated to HMRC to remove the directorship from their records. Contact us if you want help with this |
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C55326
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Periods of Account information is required for all Self Employments. Please submit. | Users can fix this. Follow these instructions to change your business settings. Let us know if you still get this error |
| Internal server error |
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This is could be because you're signed up to MTD for 2026/27 but are trying to file for 2025/26. If you want to file for 2025/26, you will need to swap back to self-assessment and can then file from untied. If you're not sure contact us. |
| Matching resource not found |
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This could be for a number of reasons at HMRC - it's a general error message. Contact us and we can investigate. |
| HMRC Error: The client or agent is not authorised |
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This is generally because you are NOT yet properly signed up for MTD, but have linked the software. Note that signing up for MTD is different to authorising the software. Contact us if you want us to look into this for you |
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No MTD obligations showing | This is a known issue which needs to be resolved at HMRC. Contact us if this applies to you. |
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Cannot amend HMRC benefit eg for incorrect value for state pension | You may get an error rhat you can't amend an HMRC record. You may need to create your own state benefit pension record which includes the right value. When you do your calculation before submitting, check that the right total is included (rather than adding both). |
If you get further errors then let us know.