If you are liable for the High Income Child Benefit charge you can choose to pay it in a lump sum through Self Assessment, or through your tax code from 6 April 2013.
Tax codes showing a deduction for the High Income Child Benefit charge will be issued during April 2013. They will replace any earlier tax code you may have received for the 2013-14 tax year.
If you choose to pay the tax charge through your tax code you will still need to complete a Self Assessment tax return.