What happens if there are errors in the submitted tax return?

If your tax return contains any errors or omits any of your income or gains, HMRC can charge you a penalty. Any penalty will be calculated as a percentage of the additional tax due.

To ensure you are not subject to a penalty make sure you keep accurate records and check with us if you do not understand anything in the return.

Penalties for late submission of the tax return

The deadline for submission of your electronic return is 31 January 2025. If your tax return is late there is a £100 penalty charge, even if there is no tax due.

If your tax return is still delayed you will also be charged the following:

  • Over three months late – a daily penalty of £10 up to a maximum of 90 days. 
  • Over six months late – an additional £300 or five per cent of the tax due if this is higher. 
  • Over twelve months late – a further £300 or a further five per cent of the tax due if this is higher. If information is being withheld the penalty can be increased to 100% of any tax due. 

Late payment interest and surcharges

Interest will be charged on all late payments of tax from the date the tax becomes due (31 January 2025) until it is paid. 

A 5% surcharge will also be levied on any tax for the year ended 5 April 2024 which is due by 31 January 2025, but is still unpaid at 2 March 2025. A further 5% surcharge will be levied on the amount still unpaid at 31 July 2025, and a further 5% surcharge will be levied on the amount still unpaid at 31 January 2026. You should therefore ensure that you make your payments on time, even if you have not received a demand. 

Full details can be found at: http://www.hmrc.gov.uk/payinghmrc/selfassessment.htm

Keeping records

Please sign and keep the copy of your tax return and the supporting documents in a safe place. You need to keep them until at least 31 January 2026 to prevent a possible HMRC penalty.  If you are a Sole Trader, a Partner or receive rental income it is necessary to keep them until at least 31 January 2030.

Enquiry window

The enquiry window during which HMRC are able to raise queries in connection with the return runs for 12 months from the date the return is filed. Should HMRC raise any queries which result in an additional liability, interest will run from the tax due date. 

If the return is filed late, the enquiry window is extended to 12 months following the quarter in which it is submitted (quarter dates being the end of January, April, July and October). 

Additionally, if the return is filed more than 90 days late and an enquiry subsequently raised, the costs of dealing with the enquiry will not be covered by the tax investigation service.

Please note that the enquiry window may be reopened later than the time limits indicated above, should HMRC become aware of information which has not been fully disclosed on the return. In these circumstances, HMRC can open discovery assessments for up to 4 years from the end of the tax year to which the assessment relates or up to 20 years in cases of fraud. 

Please note that discovery assessments are not covered by the tax investigation service. It is therefore important that we are in possession of full information when completing your return.

Protecting yourself against online fraud

Please be alert to any emails you may receive which purport to be from HMRC and may appear to offer a tax refund. Any such email you may receive will have been sent by a fraudster and not by HMRC. It is HMRC’s policy never to notify taxpayers of a tax refund or to ask you for any personal information by email. If you are suspicious of any email about your tax please contact your Hazlewoods representative.

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