Internal Revenue Code section 1031

A Section 1031 exchange, commonly known as a like-kind exchange, is a transaction under the 26 U.S.C. § 1031 of the Internal Revenue Code that allows owners of investment or business real estate to defer certain taxes when selling property and reinvesting the proceeds into other qualifying real property. It is most commonly used by real estate investors and property owners with low tax basis, for whom an outright sale would otherwise trigger capital gains tax and depreciation recapture.

Source: Wikipedia — Internal Revenue Code section 1031 (CC BY-SA 4.0)