28(1)Liability to a penalty for a failure does not arise if the person who would otherwise be liable to that penalty satisfies HMRC or (on an appeal notified to the tribunal) the tribunal that the person had a reasonable excuse for that failure.U.K.
(2)For the purposes of this paragraph—
(a)an insufficiency of funds is not a reasonable excuse unless attributable to events outside the person's control,
(b)where the person relies on another person to do anything, that cannot be a reasonable excuse—
(i)unless the first person took reasonable care to avoid the failure, or
(ii)if the first person is a UK group or UK sub-group, where the person relied on is another member of the group or sub-group,
(c)where the person had a reasonable excuse but the excuse has ceased, the person is to be treated as having continued to have the excuse if the failure is remedied without unreasonable delay after the excuse ceased.