CH402708 - Charging Penalties: establishing penalty behaviour: evaluating evidence: evidence of a reasonable excuse for non-deliberate failure or VAT or excise wrongdoing
Detailed technical guidance about reasonable excuse starts at CH160000.
A claim for reasonable excuse must be distinguished from a claim for special reduction, see
CH73400 for failure to notify
CH95300 for wrongdoing
CH63400 for failure to file on time.
It is for the person to demonstrate that they had a reasonable excuse for a non-deliberate failure or VAT or excise wrongdoing and that, when the excuse ceased to apply, they put right their failure or action without unreasonable delay.