You can apply in writing or by using HMRC’S online service to reduce the amounts of income tax payable on account of your self-assessment tax liability.
If applying in writing, send details of:
• how much you want to reduce the payments to; and
• the reason why you think your tax liability will be less than the existing payments on account. For example, the income on which you pay tax through
self-assessment, say dividends, is lower than for the previous year or you’re entitled to more tax deductions say, for additional pension contributions.
You should address your application to the HMRC office shown on your most recent tax statement of account.
Alternatively, you can complete an application online, print and send it to HMRC. To start your application, go to:
To use the online service, sign in to your HMRC account, choose the self-assessment service and on the following screen click “Claim to reduce payments
on account” (which is usually near the bottom of the page). Follow the on-screen instructions from there.