TITLE 86: REVENUE
CHAPTER I: DEPARTMENT OF REVENUE
PART 100 INCOME TAX


The General Assembly's Illinois Administrative Code database includes only those rulemakings that have been permanently adopted. This menu will point out the Sections on which an emergency rule (valid for a maximum of 150 days, usually until replaced by a permanent rulemaking) exists. The emergency rulemaking is linked through the notation that follows the Section heading in the menu.

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SUBPART A: TAX IMPOSED

SUBPART B: CREDITS

SUBPART C: NET OPERATING LOSSES OF UNITARY BUSINESS GROUPS OCCURRING PRIOR TO DECEMBER 31, 1986

SUBPART D: ILLINOIS NET LOSS DEDUCTIONS FOR LOSSES OCCURRING ON OR AFTER DECEMBER 31, 1986

SUBPART E: ADDITIONS TO AND SUBTRACTIONS FROM TAXABLE INCOME OF INDIVIDUALS, CORPORATIONS, TRUSTS AND ESTATES AND PARTNERSHIPS

SUBPART F: BASE INCOME OF INDIVIDUALS

SUBPART G: BASE INCOME OF CORPORATIONS

SUBPART H: BASE INCOME OF TRUSTS AND ESTATES

SUBPART I: BASE INCOME OF PARTNERSHIPS

SUBPART J: GENERAL RULES OF ALLOCATION AND APPORTIONMENT OF BASE INCOME

SUBPART K: COMPENSATION

SUBPART L: NON-BUSINESS INCOME OF PERSONS OTHER THAN RESIDENTS

SUBPART M: BUSINESS INCOME OF PERSONS OTHER THAN RESIDENTS

SUBPART N: ACCOUNTING

SUBPART O: TIME AND PLACE FOR FILING RETURNS

SUBPART P: COMPOSITE RETURNS

SUBPART Q: COMBINED RETURNS

SUBPART R: PAYMENTS

SUBPART S: REQUIREMENT AND AMOUNT OF WITHHOLDING

SUBPART T: AMOUNT EXEMPT FROM WITHHOLDING

SUBPART U: INFORMATION STATEMENT

SUBPART V: EMPLOYER'S RETURN AND PAYMENT OF TAX WITHHELD

SUBPART W: ESTIMATED TAX PAYMENTS

SUBPART X: COLLECTION AUTHORITY

SUBPART Y: NOTICE AND DEMAND

SUBPART Z: ASSESSMENT

SUBPART AA: DEFICIENCIES AND OVERPAYMENTS

SUBPART BB: CREDITS AND REFUNDS

SUBPART CC: INVESTIGATIONS AND HEARINGS

SUBPART DD: JUDICIAL REVIEW

SUBPART EE: DEFINITIONS

SUBPART FF: LETTER RULING PROCEDURES

SUBPART GG: MISCELLANEOUS


AUTHORITY: Implementing Section 505 of the Illinois Income Tax Act [35 ILCS 5] as authorized by Section 1401 of the Illinois Income Tax Act [35 ILCS 5] and Section 2505-795 of the Department of Revenue Law [20 ILCS 2505].

SOURCE: Filed July 14, 1971, effective July 24, 1971; amended at 2 Ill. Reg. 49, p. 84, effective November 29, 1978; amended at 5 Ill. Reg. 813, effective January 7, 1981; amended at 5 Ill. Reg. 4617, effective April 14, 1981; amended at 5 Ill. Reg. 4624, effective April 14, 1981; amended at 5 Ill. Reg. 5537, effective May 7, 1981; amended at 5 Ill. Reg. 5705, effective May 20, 1981; amended at 5 Ill. Reg. 5883, effective May 20, 1981; amended at 5 Ill. Reg. 6843, effective June 16, 1981; amended at 5 Ill. Reg. 13244, effective November 13, 1981; amended at 5 Ill. Reg. 13724, effective November 30, 1981; amended at 6 Ill. Reg. 579, effective December 29, 1981; amended at 6 Ill. Reg. 9701, effective July 26, 1982; amended at 7 Ill. Reg. 399, effective December 28, 1982; amended at 8 Ill. Reg. 6184, effective April 24, 1984; codified at 8 Ill. Reg. 19574; amended at 9 Ill. Reg. 16986, effective October 21, 1985; amended at 9 Ill. Reg. 685, effective December 31, 1985; amended at 10 Ill. Reg. 7913, effective April 28, 1986; amended at 10 Ill. Reg. 19512, effective November 3, 1986; amended at 10 Ill. Reg. 21941, effective December 15, 1986; amended at 11 Ill. Reg. 831, effective December 24, 1986; amended at 11 Ill. Reg. 2450, effective January 20, 1987; amended at 11 Ill. Reg. 12410, effective July 8, 1987; amended at 11 Ill. Reg. 17782, effective October 16, 1987; amended at 12 Ill. Reg. 4865, effective February 25, 1988; amended at 12 Ill. Reg. 6748, effective March 25, 1988; amended at 12 Ill. Reg. 11766, effective July 1, 1988; amended at 12 Ill. Reg. 14307, effective August 29, 1988; amended at 13 Ill. Reg. 8917, effective May 30, 1989; amended at 13 Ill. Reg. 10952, effective June 26, 1989; amended at 14 Ill. Reg. 4558, effective March 8, 1990; amended at 14 Ill. Reg. 6810, effective April 19, 1990; amended at 14 Ill. Reg. 10082, effective June 7, 1990; amended at 14 Ill. Reg. 16012, effective September 17, 1990; emergency amendment at 17 Ill. Reg. 473, effective December 22, 1992, for a maximum of 150 days; amended at 17 Ill. Reg. 8869, effective June 2, 1993; amended at 17 Ill. Reg. 13776, effective August 9, 1993; recodified at 17 Ill. Reg. 14189; amended at 17 Ill. Reg. 19632, effective November 1, 1993; amended at 17 Ill. Reg. 19966, effective November 9, 1993; amended at 18 Ill. Reg. 1510, effective January 13, 1994; amended at 18 Ill. Reg. 2494, effective January 28, 1994; amended at 18 Ill. Reg. 7768, effective May 4, 1994; amended at 19 Ill. Reg. 1839, effective February 6, 1995; amended at 19 Ill. Reg. 5824, effective March 31, 1995; emergency amendment at 20 Ill. Reg. 1616, effective January 9, 1996, for a maximum of 150 days; amended at 20 Ill. Reg. 6981, effective May 7, 1996; amended at 20 Ill. Reg. 10706, effective July 29, 1996; amended at 20 Ill. Reg. 13365, effective September 27, 1996; amended at 20 Ill. Reg. 14617, effective October 29, 1996; amended at 21 Ill. Reg. 958, effective January 6, 1997; emergency amendment at 21 Ill. Reg. 2969, effective February 24, 1997, for a maximum of 150 days; emergency expired July 24, 1997; amended at 22 Ill. Reg. 2234, effective January 9, 1998; amended at 22 Ill. Reg. 19033, effective October 1, 1998; amended at 22 Ill. Reg. 21623, effective December 15, 1998; amended at 23 Ill. Reg. 3808, effective March 11, 1999; amended at 24 Ill. Reg. 10593, effective July 7, 2000; amended at 24 Ill. Reg. 12068, effective July 26, 2000; emergency amendment at 24 Ill. Reg. 17585, effective November 17, 2000, for a maximum of 150 days; amended at 24 Ill. Reg. 18731, effective December 11, 2000; amended at 25 Ill. Reg. 4640, effective March 15, 2001; amended at 25 Ill. Reg. 4929, effective March 23, 2001; amended at 25 Ill. Reg. 5374, effective April 2, 2001; amended at 25 Ill. Reg. 6687, effective May 9, 2001; amended at 25 Ill. Reg. 7250, effective May 25, 2001; amended at 25 Ill. Reg. 8333, effective June 22, 2001; amended at 26 Ill. Reg. 192, effective December 20, 2001; amended at 26 Ill. Reg. 1274, effective January 15, 2002; amended at 26 Ill. Reg. 9854, effective June 20, 2002; amended at 26 Ill. Reg. 13237, effective August 23, 2002; amended at 26 Ill. Reg. 15304, effective October 9, 2002; amended at 26 Ill. Reg. 17250, effective November 18, 2002; amended at 27 Ill. Reg. 13536, effective July 28, 2003; amended at 27 Ill. Reg. 18225, effective November 17, 2003; emergency amendment at 27 Ill. Reg. 18464, effective November 20, 2003, for a maximum of 150 days; emergency expired April 17, 2004; amended at 28 Ill. Reg. 1378, effective January 12, 2004; amended at 28 Ill. Reg. 5694, effective March 17, 2004; amended at 28 Ill. Reg. 7125, effective April 29, 2004; amended at 28 Ill. Reg. 8881, effective June 11, 2004; emergency amendment at 28 Ill. Reg. 14271, effective October 18, 2004, for a maximum of 150 days; amended at 28 Ill. Reg. 14868, effective October 26, 2004; emergency amendment at 28 Ill. Reg. 15858, effective November 29, 2004, for a maximum of 150 days; amended at 29 Ill. Reg. 2420, effective January 28, 2005; amended at 29 Ill. Reg. 6986, effective April 26, 2005; amended at 29 Ill. Reg. 13211, effective August 15, 2005; amended at 29 Ill. Reg. 20516, effective December 2, 2005; amended at 30 Ill. Reg. 6389, effective March 30, 2006; amended at 30 Ill. Reg. 10473, effective May 23, 2006; amended by 30 Ill. Reg. 13890, effective August 1, 2006; amended at 30 Ill. Reg. 18739, effective November 20, 2006; amended at 31 Ill. Reg. 16240, effective November 26, 2007; amended at 32 Ill. Reg. 872, effective January 7, 2008; amended at 32 Ill. Reg. 1407, effective January 17, 2008; amended at 32 Ill. Reg. 3400, effective February 25, 2008; amended at 32 Ill. Reg. 6055, effective March 25, 2008; amended at 32 Ill. Reg. 10170, effective June 30, 2008; amended at 32 Ill. Reg. 13223, effective July 24, 2008; amended at 32 Ill. Reg. 17492, effective October 24, 2008; amended at 33 Ill. Reg. 1195, effective December 31, 2008; amended at 33 Ill. Reg. 2306, effective January 23, 2009; amended at 33 Ill. Reg. 14168, effective September 28, 2009; amended at 33 Ill. Reg. 15044, effective October 26, 2009; amended at 34 Ill. Reg. 550, effective December 22, 2009; amended at 34 Ill. Reg. 3886, effective March 12, 2010; amended at 34 Ill. Reg. 12891, effective August 19, 2010; amended at 35 Ill. Reg. 4223, effective February 25, 2011; amended at 35 Ill. Reg. 15092, effective August 24, 2011; amended at 36 Ill. Reg. 2363, effective January 25, 2012; amended at 36 Ill. Reg. 9247, effective June 5, 2012; amended at 37 Ill. Reg. 5823, effective April 19, 2013; amended at 37 Ill. Reg. 20751, effective December 13, 2013; recodified at 38 Ill. Reg. 4527; amended at 38 Ill. Reg. 9550, effective April 21, 2014; amended at 38 Ill. Reg. 13941, effective June 19, 2014; amended at 38 Ill. Reg. 15994, effective July 9, 2014; amended at 38 Ill. Reg. 17043, effective July 23, 2014; amended at 38 Ill. Reg. 18568, effective August 20, 2014; amended at 38 Ill. Reg. 23158, effective November 21, 2014; emergency amendment at 39 Ill. Reg. 483, effective December 23, 2014, for a maximum of 150 days; amended at 39 Ill. Reg. 1768, effective January 7, 2015; amended at 39 Ill. Reg. 5057, effective March 17, 2015; amended at 39 Ill. Reg. 6884, effective April 29, 2015; amended at 39 Ill. Reg. 15594, effective November 18, 2015; amended at 40 Ill. Reg. 1848, effective January 5, 2016; amended at 40 Ill. Reg. 10925, effective July 29, 2016; amended at 40 Ill. Reg. 13432, effective September 7, 2016; amended at 40 Ill. Reg. 14762, effective October 12, 2016; amended at 40 Ill. Reg. 15575, effective November 2, 2016; amended at 41 Ill. Reg. 4193, effective March 27, 2017; amended at 41 Ill. Reg. 6379, effective May 22, 2017; amended at 41 Ill. Reg. 10662, effective August 3, 2017; amended at 41 Ill. Reg. 12608, effective September 21, 2017; amended at 41 Ill. Reg. 14217, effective November 7, 2017; emergency amendment at 41 Ill. Reg. 15097, effective November 30, 2017, for a maximum of 150 days; amended at 42 Ill. Reg. 4953, effective February 28, 2018; amended at 42 Ill. Reg. 6451, effective March 21, 2018; recodified Subpart H to Subpart G at 42 Ill. Reg. 7980; amended at 42 Ill. Reg. 17852, effective September 24, 2018; amended at 42 Ill. Reg. 19190, effective October 12, 2018; amended at 43 Ill. Reg. 727, effective December 18, 2018; amended at 43 Ill. Reg. 10124, effective August 27, 2019; amended at 44 Ill. Reg. 2363, effective January 17, 2020; amended at 44 Ill. Reg. 2845, effective January 30, 2020; emergency amendment at 44 Ill. Reg. 4700, effective March 4, 2020, for a maximum of 150 days; emergency expired July 31, 2020; amended at 44 Ill. Reg. 10907, effective June 10, 2020; emergency amendment at 44 Ill. Reg. 11208, effective June 17, 2020, for a maximum of 150 days; emergency expired November 13, 2020; amended at 44 Ill. Reg. 17414, effective October 13, 2020; amended at 45 Ill. Reg. 2006, effective January 29, 2021; amended at 45 Ill. Reg. 5523, effective April 15, 2021; amended at 46 Ill. Reg. 13312, effective July 12, 2022; amended at 46 Ill. Reg. 14550, effective August 2, 2022; amended at 46 Ill. Reg. 15317, effective August 24, 2022; amended at 46 Ill. Reg. 18102, effective October 26, 2022; amended at 47 Ill. Reg. 1402, effective January 10, 2023; amended at 47 Ill. Reg. 2093, effective January 24, 2023; amended at 47 Ill. Reg. 5726, effective April 4, 2023; amended at 47 Ill. Reg. 6030, effective April 12, 2023; amended at 47 Ill. Reg. 13669, effective September 11, 2023; emergency amendment at 47 Ill. Reg. 17214, effective November 6, 2023, for a maximum of 150 days; amended at 48 Ill. Reg. 1677, effective January 10, 2024; amended at 48 Ill. Reg. 2243, effective January 29, 2024; amended at 48 Ill. Reg. 4433, effective March 11, 2024; amended at 48 Ill. Reg. 10281, effective June 25, 2024; amended at 48 Ill. Reg. 10846, effective July 11, 2024.