35 ILCS 30/15
To the extent authorized by Section 25 of this Act, for taxable years beginning on or after January 1, 2010 and ending on or before December 31, 2015, there shall be allowed a tax credit against the tax imposed by subsections (a) and (b) of Section 201 of the Illinois Income Tax Act in an amount equal to 25% of qualified expenditures incurred by a qualified taxpayer during the taxable year in the restoration and preservation of a qualified historic structure pursuant to a qualified rehabilitation plan, provided that the total amount of such expenditures (i) must equal $5,000 or more, and (ii) must exceed 50% of the purchase price of the property. If the amount of any tax credit awarded under this Act exceeds the qualified taxpayer's income tax liability for the year in which the qualified rehabilitation plan was placed in service, the excess amount may be carried forward for deduction from the taxpayer's income tax liability in the next succeeding year or years until the total amount of the credit has been used, except that a credit may not be carried forward for deduction after the tenth taxable year after the taxable year in which the qualified rehabilitation plan was placed in service. To obtain a tax credit pursuant to this Act, an application must be made to the Department no later than 6 months after the effective date of this Act. The Department, in consultation with the Department of Natural Resources , shall determine the amount of eligible rehabilitation costs and expenses. The Department of Natural Resources shall determine whether the rehabilitation is consistent with the standards of the Secretary of the United States Department of the Interior for rehabilitation. Upon completion and review of the project, the Department shall issue a certificate in the amount of the eligible credits. At the time the certificate is issued, an issuance fee up to the maximum amount of 2% of the amount of the credits issued by the certificate may be collected from the applicant to administer the Act. If collected, this issuance fee shall be evenly divided between the Department and the Department of Natural Resources . The taxpayer must attach the certificate to the tax return on which the credits are to be claimed.
35 ILCS 30/15