Amends the Property Tax Code. Provides that certain property may be certified by the Department of Revenue as containing a megaproject. Provides that a "megaproject" is a project with respect to which a company makes a specified investment during a specified investment period. Provides that the megaproject property is eligible for an assessment freeze. Provides that megaproject property may be granted an abatement. Provides that a company that operates a megaproject shall enter into an agreement with an oversight board established by the local municipality and local taxing districts to make certain special payments. Amends the Use Tax Act, the Service Use Tax Act, the Service Occupation Tax Act, and the Retailers' Occupation Tax Act. Provides that qualified tangible personal property used in the construction or operation of a megaproject is exempt from the taxes imposed under those Acts. Effective June 1, 2024.