| Date | IP Address |
| 2024-05-30 | 35.178.121.74 (ClassC) |
| 2024-06-10 | 18.133.149.198 (ClassC) |
| 2025-02-23 | 3.10.89.70 (ClassC) |
| 2025-03-14 | 3.11.204.199 (ClassC) |
| 2025-04-28 | 18.135.82.191 (ClassC) |
| 2025-05-04 | 13.42.1.129 (ClassC) |
| Date | Domain | IP |
| govuknotify.de-sina3.communications.national.nhs.uk | 2024-05-30 | 13.43.187.93 |
| api.de-jara8.communications.national.nhs.uk | 2024-05-30 | 13.43.158.227 |
| api.dev-nhsapp.communications.national.nhs.uk | 2024-12-27 | 3.11.121.12 |
| api.uat-letters.communications.national.nhs.uk | 2024-05-30 | 35.178.121.74 |
| govuknotify.uat-letters.communications.national.nhs.uk | 2024-05-30 | 13.42.117.209 |