When a return has been submitted by a taxpayer, HMRC may amend
it to correct any obvious errors or mistakes (TMA70/S9ZB). This
could include correction of arithmetic errors or errors of
principle.
There is no right of appeal against such a correction but
there is a right of rejection under TMA70/S9ZB (4). The taxpayer
can reject the correction within 30 days of its issue by giving a
notice of rejection to the officer of Revenue & Customs who
gave the notice of correction. If the taxpayer rejects the
correction the self assessment is put back to the original
figures.
