| Date | IP Address |
| 2016-02-19 | 23.35.16.199 (ClassC) |
| 2018-12-09 | 23.1.133.55 (ClassC) |
| 2023-08-25 | 104.86.253.111 (ClassC) |
| 2024-01-09 | 23.37.208.102 (ClassC) |
| 2024-03-13 | 23.223.223.107 (ClassC) |
| 2024-03-20 | 23.64.184.84 (ClassC) |
| 2024-07-01 | 104.92.255.55 (ClassC) |
| 2024-10-01 | 23.213.53.51 (ClassC) |
| 2024-10-08 | 173.222.249.18 (ClassC) |
| 2024-10-18 | 23.46.23.139 (ClassC) |
| 2024-10-31 | 23.221.22.115 (ClassC) |
| 2024-11-12 | 23.212.185.158 (ClassC) |
| 2024-11-12 | 23.222.241.7 (ClassC) |
| 2024-12-18 | 184.28.29.196 (ClassC) |
| 2024-12-20 | 23.216.145.68 (ClassC) |
| 2025-03-12 | 104.119.189.26 (ClassC) |
| 2025-03-14 | 23.210.244.151 (ClassC) |
| 2025-03-16 | 184.28.194.32 (ClassC) |
| 2025-09-07 | 23.41.4.83 (ClassC) |
| 2025-09-27 | 23.46.17.179 (ClassC) |
| 2025-10-01 | 23.46.17.190 (ClassC) |
| 2025-11-21 | 23.216.147.132 (ClassC) |
| 2026-02-14 | 23.216.147.141 (ClassC) |
| 2026-02-22 | 23.41.4.81 (ClassC) |
| Date | Domain | IP |
| apps2.irs.gov | 2014-05-11 | 198.47.108.64 |
| la1.www4.irs.gov | 2023-08-25 | 104.86.253.111 |
| sa1.www4.irs.gov | 2023-08-25 | 104.86.253.151 |
| la2.www4.irs.gov | 2023-08-25 | 104.86.253.111 |
| sa2.www4.irs.gov | 2023-08-25 | 104.86.253.151 |
| la3.www4.irs.gov | 2023-08-25 | 104.86.245.147 |
| sa3.www4.irs.gov | 2023-08-25 | 104.86.245.147 |
| la4.www4.irs.gov | 2023-08-25 | 104.86.245.147 |
| sa4.www4.irs.gov | 2023-08-25 | 104.86.245.147 |
| la.www4.irs.gov | 2023-08-25 | 104.86.253.111 |