High Income Child Benefit Charge - Tax Code Change

I recently completed SA purely for the purposes of sorting the High-Income Child Benefit Charge. Total owed came to £466, I opted for this to be collected via PAYE however my tax code has now changed so I am being taxed an extra £182/month from month 7 onwards. This will overpay this amount due for 22-23 by over £600. How come this is the case?

Hi,
Your current code will be adjusted to collect the HICBC for the 2023/24 tax year so that when you submit your 2023/24 tax return there should not be a large balance to pay.
The balance from 2022/23 £466 will be collected in your 2024/25 code. If you do not want the HICBC collected in your 2023/24 code and would rather pay at the tax year end through your Self Assessment you can contact HMRC to amend your current code:
Self Assessment: general enquiries
Thank you.

I am completing SA for 22/23 for non payroll BIK, there is a tax due because of the BIK, do I pay it with SA return? I noticed that my 23/24 PAYE code has been adjusted due to the 22/23 BIK, is that double tax payment? One via 22/23 SA return and others via additional payment through 23/24 PAYE code adjustment. Can you clarify the situation? Thanks

Hi Taxtax,
You would need to declare the BIK on your Self Assessment tax return.
Your 2023/24 tax code has been adjusted to collect tax on the BIK in the current tax year.
You will not pay tax on the BIK twice as the tax paid is for 2 different tax years. 
Thank you.