Googled that for ya

Both properties must be similar enough to qualify as "like-kind."  Like-kind property is property of the same nature, character or class.  Quality or grade does not matter. Most real estate will be like-kind to other real estate.  For example, real property that is improved with a residential rental house is like-kind to vacant land.  One exception for real estate is that property within the United States is not like-kind to property outside of the United States.  Also, improvements that are conveyed without land are not of like kind to land.

https://www.irs.gov/newsroom/like-kind-exchanges-under-irc-code-section-1031