Hi richakn knight,
Yes your parents can send a cheque on your behalf they must write your National Insurance (NI) Number on the front of the cheque so that our banking teams can process it to your NI record.
If you have applied (via CF83) from abroad to pay voluntary National Insurance Contributions (NICs) your reply of acceptance should have provided you with ways to pay.
If you have not applied to pay voluntary NICs please read the NI38 leaflet see: Social Security abroad: NI38
and complete a CF83.
Paying Voluntary NICs from abroad you don’t need a 18 digit reference. This is only for UK Class 3 payments of Voluntary NICs.
Please note the Personal Tax Account automatically defaults to UK class 3 and doesn’t show a different rate for those customers abroad.
You must have had confirmation that paying voluntary NICs will increase your state pension entitlement.
The current deadline of the 5 April 2023 has been extended to 31 July 2023.