Mark McLaughlin warns that injury and illness may not be accepted as reasonable excuses for failing to meet tax obligations.
Everyone suffers illness (or injury) from time to time. Covid-19 is a stark reminder of how fragile life can be.
For tax purposes, illness can result in tax compliance failures. However, penalties for late tax returns and payments do not apply if there is a reasonable excuse for the compliance failure, provided the failure is remedied without unreasonable delay after the excuse ceased.
Is that ‘reasonable’?
There is no statutory definition of ‘reasonable excuse’ (although insufficiency of funds is specifically excluded unless attributable to events outside the person’s control).
However, In Perrin v Revenue and Customs  UKUT 156 (TC)