There are two different deadlines depending on which procedure you follow:
Internet filing – the time limit for filing a tax return is normally 31 January in the following year, thus, for example, the 2022/23 return should be filed by 31 January 2024
paper returns – have a deadline of 31 October, for example, the 2022/23 return would be due by 31 October 2023
The deadlines above apply where taxpayers calculate their own tax liability or leave it to HMRC.
If a tax return isn’t issued by HMRC, and you owe income or capital gains tax (CGT) for any year you must notify HMRC of this within six months of the end of the tax year, i.e., by 5 October). Individuals do not have to fill in the CGT pages if their chargeable gains do not exceed the annual exempt amount, unless sale proceeds exceed four times the exempt amount, or they have allowable losses.
HMRC can issue simplified tax returns if you have simpler tax affairs. These, which don’t include the option to calculate the tax bill, are due for filing by 31 October and can’t be filed electronically.
If the notice to complete a return is sent after 31 July, the taxpayer has three months from the date of the notice to file a paper return. If filing online, the usual deadline of 31 January will be extended to three months after the date of the notice, if that’s later.
Self-assessment tax payment
Where less than £3,000 is owed the tax can be paid by via a later year’s PAYE deduction. This is achieved by adjusting your tax code number. To do this your return must be filed by 31 October if filing a paper return or electronically by 30 December following the end of the tax year to which the underpayment relates.
Where tax after taking account of PAYE and other deductions at source is payable according to your SA, payment is due as follows:
31 January 2023 – first payment on account for 2022/23, equal to 50% of the final 2021/22/ income tax and Class 4 NI liability (after taking account of tax deducted at source)
31Â July 2023 – second payment on account for 2022/23, equal to the first payment of account
31 January 2024 – known as the “balancing payment†total income tax, Class 4 NI and CGT liability for 2022/23 less payments made on account and any, tax deducted at source. A first payment on account for 2023/24 will (usually) also be due.