| Date | IP Address |
| 2022-07-13 | 54.65.203.9 (ClassC) |
| 2025-10-24 | 3.115.168.176 (ClassC) |
| 2025-11-10 | 18.176.239.148 (ClassC) |
| 2026-01-06 | 54.150.175.125 (ClassC) |
| 2026-02-05 | 35.77.140.160 (ClassC) |
| Date | Domain | IP |
| m.c21bank.co.jp | 2025-10-24 | 57.181.243.246 |
| www.c21bank.co.jp | 2025-10-24 | 3.115.168.176 |