45 & 180-Day Deadline Calculator
Sell your investment property and the IRS clock starts the next day. Enter your closing date to see your two hard 1031 deadlines — the day you must identify replacements, and the day your exchange must close.
Your sale details
The date the property you sold transferred to the buyer. Day 1 of your exchange is the next calendar day.
For a reverse exchange, the same 45/180-day periods run from the date the parked property is acquired by the Exchange Accommodation Titleholder.
Your deadlines
The two clocks of a 1031 exchange
When you sell investment real estate in a 1031 exchange, the IRS gives you two non-negotiable windows, both starting the day after your relinquished property closes:
- 45-Day Identification Period. You have 45 calendar days to formally identify, in writing, the replacement property or properties you may acquire.
- 180-Day Exchange Period. You have 180 calendar days to close on one or more of the identified properties and complete the exchange.
Counting the days
Both periods are counted in calendar days, not business days. The day of the sale is day zero; counting begins the following day. The 45-day and 180-day deadlines run concurrently — the 45 days are part of the same 180.
The year-end trap
The 180-day period actually ends on the earlier of 180 days or the due date of your income tax return for the year of the sale. If you close late in the year, your return may be due before your 180th day — so you must file for an extension to preserve the full period. This calculator flags that automatically.
This tool is for general educational purposes only. It estimates calendar deadlines and is not tax or legal advice. Deadlines can be affected by IRS disaster relief, tax-return due dates, and the specific structure of your transaction. Always confirm dates with your qualified intermediary and CPA before acting.