Get Illinois 1120 Form

Get Illinois 1120 Form

The Illinois 1120 form is the Corporation Income and Replacement Tax Return required for corporations operating in Illinois. This form is essential for reporting income and calculating taxes owed for the specified tax year. Ensure you complete the form accurately to meet your tax obligations by clicking the button below.

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The Illinois 1120 form, officially known as the Corporation Income and Replacement Tax Return, serves as a crucial document for corporations operating in the state. This form is specifically designed for tax years ending on or after December 31, 2020, and it encompasses a variety of essential components that businesses must navigate. Corporations must provide their legal business name, mailing address, and details regarding their tax year. The form also requires the identification of whether it is the corporation's first or final return, alongside any necessary attachments such as federal forms and schedules. Understanding how to accurately report income, deductions, and credits is vital, as the form guides users through calculating their base income or loss, determining the appropriate apportionment for Illinois, and ultimately figuring out their net income and taxes owed. Additionally, corporations need to be aware of specific requirements for various types of businesses, including unitary filers and foreign insurers. Completing the Illinois 1120 form accurately is not just a matter of compliance; it plays a significant role in ensuring that businesses meet their tax obligations while taking advantage of available deductions and credits.

Document Breakdown

Fact Name Description
Purpose The Illinois 1120 form is used by corporations to report income and calculate the replacement tax due to the state.
Filing Period This form applies to tax years ending on or after December 31, 2020, and before December 31, 2021.
Governing Law The form is authorized under the Illinois Income Tax Act, which outlines the legal requirements for corporate taxation in Illinois.
Due Dates Corporations must refer to the instructions for specific due dates for filing the IL-1120 form.
Payment Instructions If taxes are owed, payment can be made electronically at Tax.Illinois.gov or by mailing a completed Form IL-1120-V with a check.

Common PDF Forms

Misconceptions

  • Misconception 1: The Illinois 1120 form is only for corporations.
  • This form is specifically designed for corporations, but it may also apply to certain partnerships and S corporations under specific circumstances.

  • Misconception 2: All businesses must file the Illinois 1120 form.
  • Not every business entity is required to file this form. Only those meeting certain criteria, such as being a corporation or a specific type of partnership, must file.

  • Misconception 3: The due date for filing is the same for all businesses.
  • The filing due date can vary based on whether the business operates on a calendar year or a fiscal year. Always check the instructions for your specific due date.

  • Misconception 4: You can file the Illinois 1120 form without attaching federal forms.
  • Many lines on the Illinois 1120 require information from your federal tax return. Failing to attach the necessary federal forms may lead to delays or penalties.

  • Misconception 5: You do not need to report nonbusiness income on the Illinois 1120.
  • Nonbusiness income must be reported, especially if you are making the business income election. This can affect your overall tax liability.

  • Misconception 6: If you owe taxes, you can pay later without consequences.
  • Delaying payment can result in penalties and interest. It is crucial to pay any owed taxes by the due date to avoid additional charges.

  • Misconception 7: You can file the Illinois 1120 electronically or by mail without any specific requirements.
  • There are specific instructions for electronic filing and mailing. Ensure you follow these guidelines to avoid issues with your submission.

  • Misconception 8: You can use the same Illinois 1120 form for multiple tax years.
  • Each tax year has its own version of the form. Ensure you are using the correct form for the tax year you are filing.

  • Misconception 9: Completing the Illinois 1120 is straightforward and requires no professional help.
  • While some may find it manageable, the complexity of tax laws can make it beneficial to seek professional assistance to ensure accuracy and compliance.

Example - Illinois 1120 Form

Illinois Department of Revenue

*63512211W*

 

2021 Form IL-1120

 

 

Corporation Income and Replacement Tax Return

See “When should I file?” in the Form IL-1120 instructions for a list of due dates.

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.

Enter the amount you are paying.

$ _______________________

Step 1: Identify your corporation

AEnter your complete legal business name. If you have a name change, check this box.

Name:

BEnter 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:

 

CIf this is the first or final return, check the applicable box(es).

First return

 

 

 

Final return (Enter the date of termination.

 

 

 

 

 

)

 

mm dd

 

yyyy

DIf this is a final return because you sold this business, enter the date sold

(mm dd yyyy)

 

 

 

 

 

, and the new owner’s FEIN.

ECheck the box and see the instructions if your business is a:

Unitary Filer (Combined return)

Foreign insurer

FIf you completed the following, check the box and attach the federal

form(s) to this return.

Federal Form 8886 Federal Schedule M-3, Part II, Line 12

GApportionment Formulas. Mark the appropriate box or boxes and see

Apportionment Formula instructions.

Sales companies

Insurance companies

Financial organizations

Transportation companies

Federally regulated exchanges

H Check this box if you attached Illinois Schedule UB.

I Check this box if you attached the Subgroup Schedule.

J Check this box if you attached Illinois Schedule 1299-D.

K Check this box if you attached Form IL-4562.

L Check this box if you attached Illinois Schedule M (for businesses). M Check this box if you attached Schedule 80/20.

NEnter your federal employer identification number (FEIN).

OIf you are a member of a group filing a federal consolidated return, enter the FEIN of the parent.

PEnter your North American Industry Classification System (NAICS) Code. See instructions.

QEnter your corporate file (charter) number assigned to you by the Secretary of State.

REnter 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

SIf you are making the business income election to treat all nonbusiness income as business income, check this box and enter zero on Lines 24 and 32.

TCheck your method of accounting.

Cash Accrual Other

UIf you are making a discharge of indebtedness adjustment on Form IL-1120, Line 36, check this

box and attach federal Form 982 and a detailed statement.

VCheck this box if you attached Schedule INL.

WIf you annualized your income on Form IL-2220,

check this box and attach Form IL-2220.

XCheck this box if your business activity is protected under Public Law 86-272.

Y Check this box if you are a 52/53 week filer.

Attach your payment and Form IL-1120-V here.

If you owe tax on Line 67, make an electronic payment at Tax.Illinois.gov. If you must mail your payment, complete a payment voucher, Form IL-1120-V. Write your FEIN, tax year ending, and “IL-1120-V” on your check or money order and make it payable to “Illinois Department of Revenue.” Attach your voucher and payment here.

Enter the amount of your payment on the top of this page in the space provided.

If a payment is not enclosed, mail this return to:

If a payment is enclosed, mail this return to:

ILLINOIS DEPARTMENT OF REVENUE

ILLINOIS DEPARTMENT OF REVENUE

PO BOX 19048

PO BOX 19038

SPRINGFIELD IL 62794-9048

SPRINGFIELD IL 62794-9038

 

This form is authorized as outlined by the Illinois Income Tax Act. Disclosure of this

IR

NS

DR ____

Page 1 of 4

information is REQUIRED. Failure to provide information could result in a penalty.

 

 

IL-1120 (R-12/21)

 

 

 

*63512212W*

Step 2: Figure your income or loss

(Whole dollars only)

1Federal taxable income from U.S. Form 1120, Line 30.

 

Attach a copy of your federal return.

 

 

1

 

00

2

Net operating loss deduction from U.S. Form 1120, Line 29a. This amount cannot be negative.

2

 

00

3

State, municipal, and other interest income excluded from Line 1.

 

 

3

 

00

4

Illinois income and replacement tax and surcharge deducted in arriving at Line 1.

4

 

00

5

Illinois Special Depreciation addition. Attach Form IL-4562.

 

 

5

 

00

6

Related-Party Expenses additions. Attach Schedule 80/20.

 

 

6

 

00

7

Distributive share of additions. Attach Schedule(s) K-1-P or K-1-T.

 

 

7

 

00

8

Other additions. Attach Schedule M (for businesses).

 

 

8

 

00

9

Add Lines 1 through 8. This amount is your income or loss.

 

 

9

 

00

 

 

 

 

 

 

Step 3: Figure your base income or loss

 

 

 

 

 

10

Interest income from U.S. Treasury and other exempt federal obligations.

10

 

00

 

 

11River Edge Redevelopment Zone Dividend subtraction.

Attach Schedule 1299-B.

11

 

00

12River Edge Redevelopment Zone Interest subtraction.

 

Attach Schedule 1299-B.

12

 

00

 

 

13

High Impact Business Dividend subtraction. Attach Schedule 1299-B.

13

 

00

 

 

14

High Impact Business Interest subtraction. Attach Schedule 1299-B.

14

 

00

 

 

15

Contribution subtraction. Attach Schedule 1299-B.

15

 

00

 

 

16

Contributions to certain job training projects. See instructions.

16

 

00

 

 

17

Foreign Dividend subtraction. Attach Schedule J. See instructions.

17

 

00

 

 

18

Illinois Special Depreciation subtraction. Attach Form IL-4562.

18

 

00

 

 

19

Related-Party Expenses subtraction. Attach Schedule 80/20.

19

 

00

 

 

20

Distributive share of subtractions. Attach Schedule(s) K-1-P or K-1-T.

20

 

00

 

 

21

Other subtractions. Attach Schedule M (for businesses).

21

 

00

 

00

22

Total subtractions. Add Lines 10 through 21.

 

22

 

23

Base income or loss. Subtract Line 22 from Line 9.

 

23

 

00

4

AIf the amount on Line 23 is derived inside Illinois only, check this box and enter the amount from Step 3, Line 23 on Step 5, Line 35. You may not complete Step 4. (You must leave Step 4, Lines 24 through 34 blank.)

If you are a unitary filer, do not check this box. Check the box on Line B and complete Step 4.

B If any portion of the amount on Line 23 is derived outside Illinois, or you are a unitary filer, check this box and complete all lines of Step 4. (Do not leave Lines 28 through 30 blank.) See instructions.

Step 4: Figure your income allocable to Illinois

(Complete only if you checked the box on Line B, above.)

24 Nonbusiness income or loss. Attach Schedule NB.

24

 

00

25Business income or loss included in Line 23 from non-unitary partnerships, partnerships included on a Schedule UB, S corporations, trusts,

 

or estates. See instructions.

25

 

00

 

 

 

26

Add Lines 24 and 25.

 

26

 

 

00

27

Business income or loss. Subtract Line 26 from Line 23.

 

27

 

00

28

Total sales everywhere. This amount cannot be negative.

28

 

 

 

 

 

 

 

29

Total sales inside Illinois. This amount cannot be negative.

29

 

 

 

 

 

 

 

30

Apportionment Factor. Divide Line 29 by Line 28. Round to six decimal places.

30

 

 

 

 

 

 

 

31

Business income or loss apportionable to Illinois. Multiply Line 27 by Line 30.

 

31

 

 

00

32

Nonbusiness income or loss allocable to Illinois. Attach Schedule NB.

 

32

 

 

00

33Business income or loss apportionable to Illinois from non-unitary partnerships, partnerships

included on a Schedule UB, S corporations, trusts, or estates. See instructions.

33

 

00

34 Base income or loss allocable to Illinois. Add Lines 31 through 33.

34

 

00

Page 2 of 4

Printed by the authority of the state of Illinois. Web only, one copy.

IL-1120 (R-12/21)

Step 5: Figure your net income

*63512213W*

35Base income or net loss from Step 3, Line 23, or Step 4, Line 34.

36Discharge of indebtedness adjustment. Attach federal Form 982. See instructions.

37Adjusted base income or net loss. Add Lines 35 and 36. See instructions.

38Illinois net loss deduction. If Line 37 is zero or a negative amount, enter zero. Check this box and attach a detailed statement if you have merged losses.

39Net income. Subtract Line 38 from Line 37.

3500

3600

3700

3800

3900

Step 6: Figure your replacement tax after credits

40

Replacement tax. Multiply Line 39 by 2.5% (.025).

40

 

00

41

Recapture of investment credits. Attach Schedule 4255.

41

 

00

42

Replacement tax before credits. Add Lines 40 and 41.

42

 

00

43

Investment credits. Attach Form IL-477.

43

 

00

44

Replacement tax after credits. Subtract Line 43 from Line 42. If the amount is negative, enter zero.

44

 

00

Step 7: Figure your income tax after credits

45

Income tax. Multiply Line 39 by 7.0% (.07).

45

 

00

46

Recapture of investment credits. Attach Schedule 4255.

46

 

00

47

Income tax before credits. Add Lines

45 and 46.

47

 

00

48

Income tax credits. Attach Schedule

1299-D.

48

 

00

49

Income tax after credits. Subtract Line 48 from Line 47. If the amount is negative, enter zero.

49

 

00

 

 

 

 

 

 

Step 8: Figure your refund or balance due

50Replacement tax before reductions. Enter the amount from Line 44.

51Foreign Insurer replacement tax reduction. Attach Schedule INS or UB/INS. See instructions.

52Subtract Line 51 from Line 50. This is your net replacement tax.

53Income tax before reductions. Enter the amount from Line 49.

54Foreign Insurer income tax reduction. Attach Schedule INS or UB/INS. See instructions.

55Subtract Line 54 from Line 53. This is your net income tax.

56Compassionate Use of Medical Cannabis Program Act surcharge. See instructions.

57Sale of assets by gaming licensee surcharge. See instructions.

58Total net income and replacement taxes and surcharges. Add Lines 52, 55, 56, and 57.

59Underpayment of estimated tax penalty from Form IL-2220. See instructions.

60Total taxes, surcharges, and penalty. Add Lines 58 and 59.

61Payments. See instructions.

a

Credits from previous overpayments.

61a

b

Total payments made before the date this return is filed.

61b

cPass-through withholding reported to you.

 

Attach Schedule(s) K-1-P or K-1-T.

61c

d

Pass-through entity tax credit reported to you.

 

 

Attach Schedule(s) K-1-P or K-1-T.

61d

e

Illinois income tax withholding. Attach Form(s) W-2G.

61e

62Total payments. Add Lines 61a through 61e.

63Overpayment. If Line 62 is greater than Line 60, subtract Line 60 from Line 62.

64Amount to be credited forward. See instructions.

Check this box and attach a detailed statement if this carryforward is going to a different FEIN.

65Refund. Subtract Line 64 from Line 63. This is the amount to be refunded.

66Complete to direct deposit your refund.

Routing Number

 

 

 

 

 

 

 

 

 

 

 

 

Checking or

 

Savings

 

 

 

 

 

 

 

 

 

 

 

Account Number

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

5000

5100

5200

5300

5400

5500

5600

5700

5800

5900

6000

00

00

00

00

00

6200

63 00

64 00

6500

67 Tax due. If Line 60 is greater than Line 62, subtract Line 62 from Line 60. This is the amount you owe.

67

 

00

 

 

 

 

 

Step 9: Sign below - Under penalties of perjury, I state that I have examined this return and, to the best of my knowledge, it is true, correct and complete.

Sign

 

(

)

 

 

Check if the Department

Here

 

 

may discuss this return with the

Signature of authorized officer

Date (mm/dd/yyyy) Title

Phone

paid preparer shown in this step.

 

Paid

 

 

 

Check if

 

Print/Type paid preparer’s name

Paid preparer’s signature

Date (mm/dd/yyyy)

self-employed

Paid Preparer’s PTIN

Preparer

Firm’s name

 

Firm’s FEIN

 

 

Use Only

 

 

 

 

 

 

 

 

 

 

Firm’s address

 

Firm’s phone

(

)

Page 3 of 4

Enter the amount of your payment in the space provided on the top of page 1.

IL-1120 (R-12/21)

 

 

Attach supporting documents to your Form IL-1120.

*ZZZZZZZZZ*

 

 

 

 

 

 

 

 

If you completed:

Attach:

 

 

 

 

 

 

Form IL-1120

 

 

U.S. 1120, Pages 1 through 6, or equivalent

 

 

 

 

 

 

 

 

 

 

 

Step 1, Line E (unitary) only

 

 

 

 

 

 

 

 

 

 

 

 

 

Schedule UB/Subgroup Schedule

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Check the box on Form IL-1120, Step 1, Line H

 

 

 

 

 

 

Step 1, Line E (foreign insurer) only

 

 

 

 

 

 

 

 

 

 

Schedule INS

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Step 1, Line E (unitary) and (foreign insurer)

 

 

 

 

Schedule UB/Subgroup Schedule and Schedule UB/INS

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Check the box on Form IL-1120, Step 1, Line H

 

 

 

 

 

 

Step 1, Line F

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Federal Form 8886 or Federal Schedule M-3 (as applicable)

 

 

 

 

 

 

Step 1, Line U

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Federal Form 982

 

 

 

 

 

 

 

 

 

 

 

Step 1, Line V

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Schedule INL

 

 

 

 

 

 

 

 

 

 

 

Step 1, Line W

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Form IL-2220

 

 

 

 

 

 

 

 

 

 

 

Lines 5 and 18

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Form IL-4562

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Special Depreciation addition

Check the box on Form IL-1120, Step 1, Line K

 

 

 

 

 

 

Special Depreciation subtraction

 

 

 

 

 

 

 

Lines 6 and 19

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Schedule 80/20

 

 

 

 

 

 

Related-Party Expenses addition

Check the box on Form IL-1120, Step 1, Line M

 

 

 

 

 

 

Related-Party Expenses subtraction

 

 

 

 

 

 

 

Lines 7 and 20

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Schedule(s) K-1-P or K-1-T

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Distributive share of additions

 

 

 

 

 

 

 

Distributive share of subtractions

 

 

 

 

 

 

 

Lines 8 and 21

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Schedule M and any required support listed on Schedule M

 

 

 

 

 

 

 

 

 

 

 

Other additions

Check the box on Form IL-1120, Step 1, Line L

 

 

 

 

 

 

Other subtractions

 

 

 

 

 

 

 

Lines 11 through 15

 

 

 

 

 

 

 

 

 

 

 

 

Schedule 1299-B and any required support listed on Schedule

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

River Edge Redevelopment Zone

1299-B

 

 

 

 

 

 

Dividend subtraction

 

 

 

 

 

 

 

River Edge Redevelopment Zone

 

 

 

 

 

 

 

Interest subtraction

 

 

 

 

 

 

 

High Impact Business Dividend subtraction

 

 

 

 

 

 

 

High Impact Business Interest subtractions

 

 

 

 

 

 

 

Contributions subtraction

 

 

 

 

 

 

 

Line 17

Foreign Dividend Subtraction

 

 

 

 

 

 

 

 

Illinois Schedule J, and U.S. 1120, Schedule C or equivalent

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Lines 24 and 32

 

 

 

 

 

 

 

 

 

 

 

Schedule NB

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Nonbusiness income or loss

 

 

 

 

 

 

 

Nonbusiness income or loss allocable to Illinois

 

 

 

 

 

 

 

Lines 25 and 33

 

 

 

 

 

 

 

 

 

 

Schedule(s) K-1-P or K-1-T

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Business income or loss from non-unitary

 

 

 

 

 

 

 

partnerships, partnerships included on a Schedule UB,

 

 

 

 

 

 

 

S corporations, trusts, or estates

 

 

 

 

 

 

 

Business income or loss apportionable to Illinois from

 

 

 

 

 

 

 

non-unitary partnerships, partnerships included on a

 

 

 

 

 

 

 

Schedule UB, S corporations, trusts, or estates

 

 

 

 

 

 

 

Line 36 Discharge of indebtedness adjustment

 

 

 

Federal Form 982

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Check the box on Form IL-1120, Step 1, Line U

 

 

 

 

 

 

Lines 41 and 46 Recapture of investment credit

 

 

 

Schedule 4255

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Line 43

Investment credits

 

 

 

 

 

 

Form IL-477 and any required support listed on Form IL-477

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Line 48

Income tax credits

 

 

 

 

 

 

Schedule 1299-D and any required support listed in the Schedule

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1299-D instructions or Schedule 1299-I

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Check the box on Form IL-1120, Step 1, Line J

 

 

 

 

 

 

Lines 51 and 54 Foreign Insurer tax reduction

 

 

 

Schedule INS or Schedule UB/INS (for unitary filers)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Check the box on Form IL-1120, Step 1, Line E

 

 

 

 

 

 

Line 59

Underpayment of estimated tax penalty

 

 

Form IL-2220

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

If you annualized your income on Form IL-2220, Step 6,

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

check the box on Form IL-1120, Step 1, Line W

 

 

 

 

 

 

Line 61c

Pass-through withholding reported

 

 

All Schedules K-1-P and K-1-T you received showing

 

 

 

 

 

 

 

 

 

 

 

 

 

 

to you

pass-through withholding

 

 

 

 

 

 

Line 61d Pass-through entity tax credit

 

 

All Schedules K-1-P and K-1-T you received showing

 

 

 

 

 

 

 

 

 

 

 

 

 

 

reported to you

pass-through entity tax credit

 

 

 

 

 

 

Line 61e Illinois income tax withholding

 

 

 

 

 

 

 

 

 

 

 

Copies of all Forms W-2G

 

 

 

 

 

 

 

 

 

 

**Failure to attach the required documents may result in the disallowance of the corresponding line item.**

Page 4 of 4

IL-1120 (R-12/21)

Dos and Don'ts

When filling out the Illinois 1120 form, it is essential to follow specific guidelines to ensure accuracy and compliance. Here’s a list of things you should and shouldn’t do:

  • Do enter your complete legal business name accurately.
  • Do check the appropriate boxes for first or final returns.
  • Do attach all required supporting documents as specified in the instructions.
  • Do ensure your federal employer identification number (FEIN) is correct.
  • Do calculate your income or loss using whole dollars only.
  • Don’t leave any required fields blank; fill in all necessary information.
  • Don’t forget to sign and date the form before submission.
  • Don’t use negative numbers where not allowed; ensure all amounts are positive unless specified.
  • Don’t overlook the due date for filing your return; late submissions may incur penalties.
  • Don’t forget to double-check your math calculations to avoid errors.

Illinois 1120: Usage Instruction

Completing the Illinois 1120 form is essential for corporations operating in Illinois. This form is used to report income, deductions, and tax liability. To ensure accuracy, follow the steps outlined below carefully.

  1. Identify Your Corporation
    • Enter your complete legal business name.
    • Provide your mailing address and check the box if this is your first return or if your address has changed.
    • Indicate if this is your first or final return by checking the appropriate boxes.
    • If applicable, enter the date sold and the new owner’s FEIN if this is a final return due to a business sale.
    • Check the box if your business is a unitary filer or a foreign insurer.
    • Complete any additional required sections regarding attachments and codes.
  2. Figure Your Income or Loss
    • Enter your federal taxable income from U.S. Form 1120.
    • Deduct any net operating loss and other specified amounts as instructed.
    • Add any required additions to your income.
    • Calculate your total income or loss.
  3. Figure Your Base Income or Loss
    • List any interest income and other subtractions as specified.
    • Calculate your total subtractions.
    • Determine your base income or loss by subtracting total subtractions from total income.
  4. Figure Your Income Allocable to Illinois
    • If applicable, calculate nonbusiness income or loss.
    • Determine your apportionment factor based on total sales.
    • Calculate business income or loss apportionable to Illinois.
  5. Figure Your Net Income
    • Calculate your adjusted base income or net loss.
    • Subtract any Illinois net loss deduction from your adjusted base income to find net income.
  6. Figure Your Replacement Tax After Credits
    • Calculate your replacement tax based on your net income.
    • Account for any investment credits and determine your replacement tax after credits.
  7. Figure Your Income Tax After Credits
    • Calculate your income tax and account for any recaptures and credits.
    • Determine your income tax after credits.
  8. Figure Your Refund or Balance Due
    • Calculate your total taxes, surcharges, and penalties.
    • Determine total payments and overpayments.
    • Calculate the refund or balance due.
  9. Sign and Date the Return
    • Ensure the authorized officer signs the return.
    • Provide the date and any preparer information if applicable.

After completing the form, double-check all entries for accuracy. Attach any required documents and payment if necessary. Finally, submit the form to the Illinois Department of Revenue by the due date to avoid penalties.