NIM18100 - Class 1B NICs: liability: payment date for Class 1B NICs
Paragraph 13(1) of Schedule 4 to the Social Security Contributions Regulations 2001 (SSCR 2001) (SI 2001 No 1004)
The final due date for payment of Class 1B NICs is 19 October (or 22 October where paid by an approved electronic payment method) following the year to which the PAYE Settlement Agreement (PSA) applies, but payments of tax and NICs can be made at any time after the agreement is signed.
For example, the payment of Class 1B NICs in connection with a PSA agreed for the 2021 to 2022 tax year is due to be made by 19 (or 22) October 2022.