

| Entries on HMRC forms where NINOs not known | ||||
| Form | Internet (ISP) | Electronic Data (EDI) | Magnetic Media | Paper |
| P14 | Leave blank but show DOB | Leave blank but show DOB | Space filled but show DOB | Leave blank but show DOB |
| P38A | Leave Blank | Enter 'NONE' | Enter 'Not Known' | |
| P11D | Enter 'Not Known' | Enter 'NONE' | Blank space must be left | Leave Blank |
| P9D | Enter 'Not Known' | Leave Blank | ||
| P46(car) | A valid NINO must be used | Enter 'NONE' | Leave Blank | |
| P45(1) | Enter 'Not Known' | Enter 'NONE' | Leave Blank | |
| P45(3) | Enter 'Not Known' | Enter 'NONE' | Leave Blank | |
| P46 | Enter 'Not Known' | Enter 'NONE' | Leave Blank | |
Whilst every care has been taken in the compilation of these tables, the information is based on our own interpretation of the official guides and is provided for comparison purposes only. No responsibility for loss occasioned to any person or any business for action taken or refraining from action based on this information, can be accepted.