Legal Question in Real Estate Law in Illinois

Reducing it to its simplest, an attorney would need to examine your exact intent to determine if an exception applies to the Plat Act. Probably, an exception would apply. Next, it would need to be determined whether a survey is needed or desired. It would be needed if there is not a clear way to describe the exact parcel (irregular shape or wanting to use specific landmarks). Even if the parcel can be easily described (such as, "the Northerly five acres of ..."), both parties may still find it useful to have a survey in hand. Then, when you have a buyer, a typical closing can be completed.

In addition to Mr. Repay's comments, your county, or the municipality you are located in, may require you to file for a subdivision, which will require a survey too. That is more complicated, and the kind of survey that may be needed, often requires the dedication of roads, easements for utilities, etc., in addition to complying with local zoning ordinances regarding minimum lot sizes. If there are wetlands, there may be additional requirements including environmental impact studies. If the land is not currently annexed to a municipality, only county ordinances may apply. If you are seeking to make them marketable to include fire and police protection of the closest municipality, you may need to consider annexation to that municipality as well. All in all, consult with a real estate lawyer in your area who handles real estate development work in particular.