Exchange period, under IRC Section 1031, is when an exchanger or taxpayer executing a delayed exchange has 180 calendar days from the closing date of the sale of their relinquished property to complete the acquisition of the replacement property or properties. Note, however, that potential properties must be identified within 45 calendar days of sale. For instance, if an exchanger sells their relinquished property on June 1st, they would have until July 16th to formally identify potential replacement properties, but would have until November 28th to complete the acquisition of the replacement property.