If you need to submit a tax return for the first time, or who no longer need to because your circumstances have changed, then tell us by the 5 October 2023. 
You can use the free online tool on GOV.UK to check if you need to complete a tax return for 6 April 2022 to 5 April 2023 tax year. 
Further information is available in our news item and in our guidance on registering for Self Assessment and stopping Self Assessment for the self-employed.