35 ILCS 5/910

(35 ILCS 5/910) (from Ch. 120, par. 9-910)

Sec. 910. Procedure on Denial of Claim for Refund.

(a) Time for protest. Within 60 days after the denial of the
claim,
the claimant may file (i) a protest with the Department or (ii) a petition with the Illinois Independent Tax Tribunal, as provided in this subsection (a). A written protest against such
denial shall be filed with the Department in such form as the Department may by regulations prescribe, setting
forth the grounds on which such protest is based. If such a protest is filed,
the Department shall reconsider the denial and, if the taxpayer has so
requested, shall grant the taxpayer or his authorized representative a
hearing. With respect to protests filed with the Department prior to July 1, 2013 that would otherwise be subject to the jurisdiction of the Illinois Independent Tax Tribunal, the taxpayer may elect to be subject to the provisions of the Illinois Independent Tax Tribunal Act of 2012 on or after July 1, 2013, but not later than 30 days after the date on which the protest was filed.  If made, the election shall be irrevocable.

A claimant who, on or after July 1, 2013, wishes to protest a denial that is subject to the jurisdiction of the Illinois Independent Tax Tribunal  shall do so by filing a petition with the Illinois Independent Tax Tribunal pursuant to the Illinois Independent Tax Tribunal Act of 2012.

(b) Notice of decision. With respect to protests that are subject to the jurisdiction of the Department, if the taxpayer has not made an election to be subject to the provisions of the Illinois Independent Tax Tribunal Act of 2012, then as soon as practicable after such
reconsideration and hearing, if any, the Department shall issue a notice of
decision by mailing such notice by certified or registered mail. Such
notice shall set forth briefly the Department's findings of fact and the
basis of decision in each case decided in whole or in part adversely to the
claimant.

(c) Request for rehearing. Within 30 days after the mailing of a
notice of decision as provided in subsection (b), the claimant may file with the Department a written
request for rehearing in such form as the Department may by regulations
prescribe, setting forth the grounds on which rehearing is requested. In
any such case, the Department shall, in its discretion, grant either a
rehearing or Departmental review unless, within 10 days of receipt of such
request, it shall issue a denial of such request by mailing such denial to
the claimant by certified or registered mail. If rehearing or Departmental
review is granted, as soon as practicable after such rehearing or
Departmental review, the Department shall issue a notice of final decision
as provided in subsection (b).

(d) Finality of decision. If the taxpayer fails to file a timely protest or petition under subsection (a) of this Section, then the Department's notice of deficiency shall become a final assessment at the end of the 60th day after the date of issuance of the notice of deficiency. If the protest is subject to the jurisdiction of the Department, and the taxpayer does not elect to be subject to the provisions of the Illinois Independent Tax Tribunal Act of 2012, then the action of the Department on the claimant's
protest shall become final:

(1) 30 days after issuance of a notice of decision as