You must check the date from which these rules apply for
the tax or duty you aredealing with. SeeCH81011for full details.
A penalty may be appropriate where tax has been under-assessed because of the person’s (P’s) failure to send us a return, see CH81090. You must consider
P must tell you if they think the assessment is too low. Reasonable steps to tell you about the under-assessment include
P will not be liable to a penalty if they tell us that the
assessment is too low within 30 days of the date the assessment is
issued. P only has to tell us the assessment is too low. They do
not necessarily have to send us the outstanding return. You may
need to consider what other action is appropriate to obtain the
A person who sends their return in on time will not receive an assessment of estimated liability. They will have self-assessed, or declared their tax liability, and so this penalty will not apply.
This penalty could apply where, exceptionally, an IHT account is not received within the appropriate time-limits and we make a determination of the tax due.