IL-1120-ST (R-02/22) Page 1 of 5
Illinois Department of Revenue
2021 Form IL-1120-ST
Small Business Corporation Replacement Tax Return
Due on or before the 15th day of the 3rd month following the close of the tax year.
If this return is not for calendar year 2021, enter your fiscal tax year here.
Tax year beginning
20 , ending 20
month day year month day year
This form is for tax years ending on or after December 31, 2021, and before December 31, 2022.
For all other situations, see instructions to determine the correct form to use.
Step 1: Identify your small business corporation
A Enter your complete legal business name.
If you have a name change, check this box.
Name:
B Enter your mailing address.
Check this box if either of the following apply:
• this is your first return, or
• you have an address change.
C/O:
Mailing address:
City: State: ZIP:
C If this is the first or final return, check the applicable box(es).
First return
Final return (Enter the date of termination. )
mm dd yyyy
D If this is a final return because you sold this business, enter the date sold
(mm dd yyyy) , and the new owner’s FEIN
.
E Apportionment Formulas. Check the appropriate box or boxes and see
the Apportionment Formula instructions.
Financial organizations Transportation companies
Federally regulated exchanges Sales companies
F Check this box if you attached Form IL-4562.
G Check this box if you attached Illinois Schedule M (for businesses).
H Check this box if you attached Schedule 80/20.
I Check this box if you attached Schedule 1299-A.
J Check this box if you attached the Subgroup Schedule.
K Check this box if you are a 52/53 week filer.
L Check this box if you elected to file and pay Pass-through
Entity Tax. See instructions.
M If you are paying Pass-through Entity Tax and you annualized your
income on Form IL-2220, check this box and attach Form IL-2220.
Enter the amount you are paying.
$
Step 2: Figure your ordinary income or loss (Whole dollars only)
1 Ordinary income or loss, or equivalent from federal Schedule K. 1
00
2 Net income or loss from all rental real estate activities. 2
00
3 Net income or loss from other rental activities. 3
00
4 Portfolio income or loss. 4
00
5 Net IRC Section 1231 gain or loss. 5
00
6 All other items of income or loss that were not included in the computation of income or loss on
Page 1 of U.S. Form 1120-S. See instructions. Identify: ______________________________ 6
00
7 Add Lines 1 through 6. This is your ordinary income or loss. 7
00
Step 3: Figure your unmodified base income or loss
8 Charitable contributions. 8
00
9 Expense deduction under IRC Section 179. 9
00
10 Interest on investment indebtedness. 10
00
11 All other items of expense that were not deducted in the computation of ordinary income or loss on
Page 1 of U.S. Form 1120-S. See instructions. Identify: ______________________________ 11
00
12 Add Lines 8 through 11. 12
00
13 Subtract Line 12 from Line 7. This amount is your total unmodified base income or loss. 13
00
Attach your payment and Form IL-1120-ST-V here.
*32712211W*
N Enter your federal employer identification number
(FEIN).
O Check this box if you are a member of a
unitary business group, and enter the FEIN of
the member who prepared the Schedule UB,
Combined Apportionment for Unitary Business
Group. Attach Schedule UB to this return.
P Enter your North American Industry Classification
System (NAICS) Code. See instructions.
Q Enter your Illinois corporate file (charter) number
issued by the Secretary of State.
R Enter the city, state, and zip code where your
accounting records are kept. (Use the two-letter
postal abbreviation, e.g., IL, GA, etc.)
City State ZIP
S If you are making the business income election to
treat all nonbusiness income as business income,
check this box and enter zero on Lines 36 and 44.
T If you have completed the following, check the box
and attach the federal form(s) to this return.
Federal Form 8886 Federal Sch. M-3,
Part II, Line 10
U If you are making a discharge of indebtedness
adjustment on Form IL-1120-ST, Line 48,
check this box and attach federal Form 982
and a detailed statement.
V Check this box if your business activity is
protected under Public Law 86-272.
This form is authorized as outlined by the Illinois Income Tax Act. Disclosure of this
information is REQUIRED. Failure to provide information could result in a penalty.
IR NS DR
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