Boston Marathon 2025 Qualifying Window. The boston marathon registration window for the 2025 boston marathon opens on september 1, 2023, and closes on september 13, 2024. The qualifying window for the 129th boston marathon, scheduled to take place on april 21, 2025, began on september 1, 2023.

The boston marathon registration window for the 2025 boston marathon opens on september 1, 2023, and closes on september 13, 2024. This year (for boston 2024) the registration period was 9/11/23 to 9/15/23.