Businesses must file their tax returns within one year of the end of the accounting period; the return must include a self-assessment of tax liability, eliminating the need for HMRC assessment (although HMRC retains assessment powers in certain cases where it is not satisfied with the return or where the business fails to make a return).
The UK tax system can impose numerous penalties for non-compliance with the self-assessment system. These include penalties for late filing of returns, failure to keep proper records, submission of an incorrect return, commission of errors in certain documents sent to HMRC, unreasonable failure to report errors in assessments by HMRC, and failure to respond to a formal notification of information requested. from the tax authorities within the time allowed.
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