I made a mistake on my tax return; what now?

mistake,tax return,hard

Mistakes are part of life. No one likes to make them and it always feels better once they are corrected. Mistakes with your tax can seem daunting, but they can always be fixed.

If you failed to submit a tax return

If you failed to submit a tax return then the first question to ask is ‘did HMRC ask you to submit tax returns for all the year(s) you are worried about’? If so, then you may be able to fill them in and submit them anyway.

The filing date for an online tax return is currently 31 January after the end of the tax year. You can submit personal tax returns for up to three years after the filing date. HMRC will charge you late payment interest and penalties as well as the tax.

Making a voluntary disclosure

If you have more years’ returns to submit, never received any communication from HMRC asking you to submit tax returns or realised that you did not include all your income, profits or gains in your tax return then you need to make a ‘voluntary disclosure’.

A voluntary disclosure is a process by which you tell HMRC what income, gains and profits need to be taxed so that they can assess what you owe before you pay the tax and any late payment interest. Depending on what went wrong, you may also need to pay some penalties.

Making a voluntary disclosure before HMRC finds out and opens an enquiry or investigation usually results in lower tax-geared penalties and minimises the risk of prosecution or having your details published. It is often a simpler process too, compared to a full investigation.

Don’t think HMRC will find out? Think again…

If you doubt HMRC will find out – think for a moment about HMRC’s new computer system called CONNECT, which holds data on everyone including details of bank interest, salaries, etc. Soon this will automatically annually receive data on bank interest and balance from banks outside the UK. The computer identifies people for HMRC to investigate.

Seek help

As soon as you realise you need to correct your tax affairs, appoint an experienced advisor who is used to helping people in situations similar to yours. They will advise you on your options for making a disclosure, depending on your specific situation and why the problem arose.

Tax rules are complicated, so please get advice rather than trying to use HMRC’s Digital Disclosure Service yourself. An advisor can also guide you as to what penalties to expect and whether you may be able to get them suspended, as well as resolving other related issues, VAT issues, for example. They should also be able to negotiate time to pay if you cannot afford to pay HMRC in full immediately.

Helen Adams TEP is Tax Principal at BDO LLP in London, UK


An article of this kind can never provide a complete guide to the law in these areas, which may be subject to change from time to time. The opinions and suggestions made within this article should not be interpreted as specific advice in relation to any particular individual or individuals. Neither STEP, the article author or their firm accept responsibility for any loss occasioned by someone acting or refraining to act on the basis of the opinions and suggestions contained in this article. More