Tax returns: provisional or estimated figures
If you do not have the right information to be able to complete your tax return accurately, you can use a provisional or estimated figure.
If you know you have something to include on your tax return but do not yet know the correct amount, you should provide a provisional figure. This is different from an estimated figure (see below).
For example, Jean knows that she has some bank interest to include in her tax return. She thinks it was around £200, but cannot find a statement or interest certificate showing the exact amount for the tax year. It is approaching the deadline for submitting her tax return. She contacts the bank and they tell her it will take two weeks to send her the information she needs.
Jean should enter the £200 provisional figure on her tax return and tick the box that says the return includes provisional information. She should explain in the additional information box that she has contacted her bank to confirm the figures and that she expects to be able to provide the exact sum in two weeks’ time, when the statement has arrived. She should submit the return with the provisional figure, so that she does not incur a late filing penalty.
When the statement from the bank arrives, Jean will need to amend her tax return for the correct interest figure. She can either do this by writing to HMRC with the information, or – if she filed online – she can go into her Personal Tax Account and amend the form and re-submit it. If she used third party software to complete her tax return, she should use that to submit the amended tax return.
You might have lost some important documents that you needed for your tax return and can never get them back (though you should try your best to get copies, if this is possible).
If you really cannot retrieve your records, you will have to make a best guess (or estimate) at the figures you should include on your return.
If you have estimated any of the figures on your tax return, you should always tell HMRC (or ‘disclose’) what they are and why, and how you have worked out the figures you have used. Give as much information as possible – usually in the additional information text box provided on the return. This could help to protect you from HMRC later suggesting you owe more tax or trying to charge you an inaccuracy penalty. In such cases, you will need to be able to demonstrate that you took reasonable care to complete the tax return to the best of your knowledge and belief.