45 / 180 Day Calculator This 45 / 180 day calculator will help you determine your 1031 exchange deadlines. January February March April May June July August September October November December 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 2020 2021 2022 2023 2024 2025 2026 Initial sale date: 45 day identification period ends: 180 day purchase date ends: