The identification period generally starts when the relinquished property transfers.
For a deferred exchange, the IRS instructions state that replacement property generally must be identified within 45 days after transfer of the property given up. The identification must be in writing and describe the replacement property clearly enough to be recognizable, subject to the applicable regulatory rules.
The practical lesson: do not wait until Day 1.
Financing, property tours, due diligence, investment committee review and negotiations can consume the entire window. Serious exchange planning often begins before the relinquished property closes, with backup properties and decision criteria identified early.
Use the date as a control—not a strategy.
The 45-day deadline is a federal timing rule. It does not make a weak property stronger, solve financing, or replace due diligence.
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