Paragraph 11 Amendments and corrections of return
United Kingdom
An officer of Revenue and Customs may amend a return under paragraph 8 or 9 so as to correct—
obvious errors or omissions in the return (whether errors of principle, arithmetical mistakes or otherwise), and
anything else in the return that the officer has reason to believe is incorrect in the light of information available to the officer.
A correction under sub-paragraph (3) is made by notice to the person whose return it is.
No such correction may be made more than nine months after—
the day on which the return was delivered, or
if the correction is required in consequence of an amendment of the return under sub-paragraph (1), the day on which that amendment was made.
A correction under sub-paragraph (3) is of no effect if the person whose return it is gives notice rejecting the correction.