There are many reasons a tax return cannot be filed online and HMRC has released a list of those affected by software issues. I've summarised a few of them below, with help from the ICAEW's Tax Facility ...
If you discover your tax return can't be filed online, then these exclusions are a reasonable excuse for filing after the 31st of October deadline for paper returns.
HMRC doesn't usually charge a penalty if this is the case as long as the tax return is filed by the 31st of January, the usual online filing deadline and a reasonable excuse claim is included with the individual's tax return.
My professional body, the ICAEW, has produced a list of the commonest reasons a tax return cannot be filed online and this is shown below. HMRC also published a complete list of exclusions which you can read by clicking here.
>p?What ICAEW has compiled here is extensive, but not the complete list of exclusions published by HMRC. If you're planning on filing your tax return online soon and anything you've read jumps out as a red flag for you, then do get in touch as I'd be happy to advise you.
If you feel inspired to find out more about anything I've said here, do call me on 01908 774320 or leave a comment below and I'll be in touch as soon as I can.