Page 1 of 6
IL-1120-X Instructions (R-12/23)
Illinois Department of Revenue
IL-1120-X Instructions 2023
Use for tax year ending on or
after December 31, 2023 and
before December 31, 2024.
Who must le Form IL-1120-X?
You should le Form IL-1120-X, Amended Corporation Income and
Replacement Tax Return, if you are amending a previously led,
processable Form IL-1120, Corporation Income and Replacement
Tax Return, or Form IL-1120-X, for a tax year ending on or after
December 31, 1986. Your change can occur from a state or federal
change that aects items used to compute your Illinois net income,
net loss, or credits, such as
• an amendment of your federal income tax return,
• an adjustment made by the Internal Revenue Service (IRS), or
• any other recomputation or redetermination.
A separate Form IL-1120-X must be led for each tax year you need
to amend.
What if I need to change my return before the
extended due date expires?
If you led your original Form IL-1120 and a state or federal
correction or change needs to be made before the extended due
date expires (see the instructions of your original return), you should
le Form IL-1120-X. Due to the automatic extension, any return led
after the original return and on or before the extended due date will
be treated as the original return.
If you are ling Form IL-1120-X to change the election on your
original return to treat all income other than compensation as
business income, check the box in Step 1, Line Q, and provide a
written explanation indicating the change to your election in the
“Explain the changes on this return” area on Form IL-1120-X.
How long do I have to amend my return?
The amount of time you have to amend your return depends on
whether your Form IL-1120-X is being led to report a state or federal
change.
If an amended return claiming a credit or refund is led
within six months of the expiration of the statute of limitations, then
the statute of limitations will automatically be extended an additional
six months for issuing an assessment of additional tax due.
State change - If your change creates or increases the Illinois net
loss for the year, you must le Form IL-1120-X showing the increase
in order to carry the increased loss amount to another year.
If your change decreases the tax due to Illinois and you are entitled
to a refund or credit carryforward, you must le Form IL-1120-X
within
• three years after the due date of the return (including
extensions),
• three years after the date your original return was led, or
• one year after the date your Illinois tax was paid, whichever is
latest.
If your change increases the tax due to Illinois, you should le
Form IL-1120-X and pay the tax, penalty, and interest promptly.
Federal change - Do not le this amended return until you
receive a federal nalization notication from the IRS stating that
they have accepted your change, either by paying a refund, or by
nal assessment, agreement, or judgment. In order to process an
amended return due to a federal change, the Illinois Department
of Revenue (IDOR) requires proof of federal nalization. Proof of
federal nalization includes one or more of the following:
• a copy of your federal audit report (signed and dated by a
federal auditor),
• an IRS account transcript, or
• a federal refund check.
Acknowledgement that the IRS received your amended
return is not acceptable proof of federal nalization.
If your federal change decreases the tax due to Illinois and
you are entitled to a refund or credit carryforward, you must le
Form IL-1120-X within two years plus 120 days of federal nalization.
If your federal change increases the tax due to Illinois, you must
le Form IL-1120-X and pay any additional tax within 120 days of
IRS partial agreement or nalization. In order to avoid late payment
penalties, you must pay any additional tax to IDOR and attach proof
of the federal nalization date, showing the change was reported to
Illinois within 120 days of IRS acceptance, or you may be assessed a
late-payment penalty.
If you fail to notify us of your change by ling
Form IL-1120-X, we may issue a notice of deciency at any time.
Once you le your change, we may issue a notice of deciency within
two years.
What if I am amending my return due to multiple
federal adjustments?
If you are amending your original Form IL-1120 due to multiple
federal adjustments that were nalized on dierent dates, then
you must complete separate amended Illinois returns for each
federal nalization date. For example, if you receive a 2023 return
adjustment from the IRS on July 10, 2024, and in August 2024,
you amend your U.S. Form 1120 and receive federal nalization on
October 22, 2024, then you must submit one Form IL-1120-X for the
July 10, 2024, adjustments and a separate Form IL-1120-X for the
October 22, 2024, adjustments. Failure to le separate amended
returns for each federal nalization date may result in the denial of
the entire claim, a delay in processing, or the assessment of penalty
and interest.
Proof of federal nalization must be attached to your
amended return before the return will be processed.
What if my amended return involves unitary
ling?
If you are amending your original
• unitary Form IL-1120 to report a state or federal change to your
unitary income, you must le one combined Form IL-1120-X for
all members and a revised Illinois Schedule UB, Combined
Apportionment for Unitary Business Groups along with any
necessary Subgroup Schedules.
• non-unitary Form IL-1120 to be included in an existing
unitary group, you must le Form IL-1120-X, reporting a zero
tax liability, and the unitary group must le one combined
Form IL-1120-X and attach a revised Illinois Schedule UB that
includes you as a member.
What if my amended return involves an Illinois
net loss deduction (NLD)?
If you have an Illinois NLD carryforward from any loss year ending on
or after December 31, 1986, it is subtracted from and limited to base
income allocable to Illinois.
To determine your “Illinois net loss” start with federal taxable income
and apply all addition and subtraction modications, and all allocation
and apportionment provisions.
If you are carrying an Illinois NLD, refer to the “General Information”
section of Form IL-1120 Instructions and Schedule NLD or UB/NLD
Instructions for how to calculate your Illinois Net Loss Deduction.
Printed by the authority of the state of Illinois - electronic only - one copy.
General Information
Page 2 of 6
IL-1120-X Instructions (R-12/23)
Who should sign the return?
Your Form IL-1120-X must be signed by the president, vice president,
treasurer, or any other ocer duly authorized to sign the return. If
you paid someone (other than a regular employee of the taxpayer,
such as a clerk, secretary, or bookkeeper) to prepare your return,
that individual must provide a signature, date the return, enter the
preparer tax identication number (PTIN) issued to them by the
Internal Revenue Service, and provide their rm’s name, federal
employer identication number (FEIN), address, and phone number.
Can a reasonable facsimile be used?
In general, you must obtain and use forms prescribed by the Illinois
Department of Revenue (IDOR). Separate statements not on forms
provided or approved by IDOR will not be accepted and you will
be asked for appropriate documentation. Failure to comply with
this requirement may result in failure to le penalties, a delay
in the processing of your return, or a delay in the generation
of any overpayment. Additionally, failure to submit appropriate
documentation when requested may result in a referral to our Audit
Bureau for compliance action.
Corporations must complete Form IL-1120-X. Do not send a
computer printout with line numbers and dollar amounts attached
to a blank copy of the return. Computer generated printouts are
not acceptable, even if they are in the same format as IDOR forms.
Computer generated forms from an IDOR-approved software
developer are acceptable.
What are the penalties and interest?
Penalties — You will owe
• a late-ling penalty if you do not le a processable return by
the extended due date;
• a late-payment penalty if you do not pay the tax you owe by
the original due date of the return;
• a late-payment penalty for underpayment of estimated tax
if you were required to make estimated tax payments and failed
to do so, or failed to pay the required amount by the payment
due date;
• a bad check penalty if your remittance is not honored by your
nancial institution;
• a cost of collection fee if you do not pay the amount you owe
within 30 days of the date printed on your bill.
Interest — The interest rate is the federal underpayment rate, which
is set by the IRS under Internal Revenue Code (IRC) Section 6621.
For more information about penalties and interest, see
Publication 103, Penalties and Interest for Illinois Taxes, available at
tax.illinois.gov.
For amended tax returns led on or after
January 1, 2024, a late payment penalty will be assessed for any
amended return not led and the resulting liability not paid within
120 days of the federal change. See 35 ILCS 735/3-3(b-25) for more
information.
What must I attach to my Form IL-1120-X?
This form must contain a complete explanation of the reasons for
ling the claim or amendment. You must attach proof of the federal
nalization date and any schedules, forms, breakdowns, statements,
or other documentation required to support your claim. If Form
IL-1120-X is submitted without the proper attachments, it may be
partially or totally denied.
Examples of federal nalization include a copy of one or more of the
following items:
• your federal refund check
• your audit report from the IRS
• your federal transcript verifying your federal taxable income
If you are ling Form IL-1120-X because
• you led a U.S. Form 1120-X or U.S. Form 1139 and your tax
due to Illinois decreases, you must attach proof of the federal
nalization date, include a copy of that federal return, plus
any other related forms, schedules, or attachments, including
a signed and dated copy of any federal report of income tax
examination changes (e.g., Form 4549A and B), if applicable.
• you led a U.S. Form 1120-X and your tax due to Illinois
increases, you must attach proof of the federal nalization
date, including a signed and dated copy of any federal report
of income tax examination changes (e.g., Form 4549A and
B), if applicable, showing the change was reported to Illinois
within 120 days of IRS acceptance, or you may be assessed a
late-payment penalty.
• of a change by the IRS, you must include all copies of the
federal examining ocer’s reports, including preliminary,
revised, corrected, and superseding reports, and a signed and
dated copy of any federal report of income tax examination
changes (e.g., Form 4549A and B), if applicable.
• you copied information incorrectly from your U.S. Form 1120
onto your Form IL-1120, you must include a copy of your
U.S. Form 1120.
• of a change in, or audit of, another state’s tax return, you
must include a copy of the other state’s corrected return or the
examining ocer’s reports.
• of changes reported on a revised Schedule K-1-P or K-1-T (or
any equivalent document) you received, you must include a
copy of the revised Schedule(s) K-1-P or K-1-T (or equivalent
document).
• of changes, other than those described above, see
Form IL-1120 Instructions and any schedules for the year you
are changing to determine what attachments you must provide.
Should I round?
You must round the dollar amounts on Form IL-1120-X to
whole-dollar amounts. To do this, you should drop any amount less
than 50 cents and increase any amount of 50 cents or more to the
next higher dollar.
Where should I le?
Mail your Form IL-1120-X to:
ILLINOIS DEPARTMENT OF REVENUE
PO BOX 19016
SPRINGFIELD IL 62794-9016
What if I need additional assistance or forms?
• For assistance, forms, or schedules, visit our website at
tax.illinois.gov or scan the QR code provided.
• Write us at:
ILLINOIS DEPARTMENT OF REVENUE
PO BOX 19001
SPRINGFIELD IL 62794-9001
• Call 1 800 732-8866 or 217 782-3336 (TTY at 1 800 544-5304).
• Visit a taxpayer assistance oce - 8:00 a.m. to 5:00 p.m.
(Springeld oce) and 8:30 a.m. to 5:00 p.m. (all other oces),
Monday through Friday.
Page 3 of 6
IL-1120-X Instructions (R-12/23)
For instructions regarding completion of Steps 1 through 7, refer
to the Form IL-1120 Instructions and schedules for the year being
amended.
Specic instructions for most of the lines are provided on the
following pages. If a specic line is not referenced, follow the
instructions on the form.
Enter the tax year you are amending in the space provided at the top
of Form IL-1120-X.
Step 1: Identify your corporation
A — Type or print your legal business name. If you have a name
change from your original return, check the corresponding box.
B — Type or print your mailing address.
C — If you are ling an Illinois combined unitary return, check this
box and attach a complete and corrected Illinois Schedule UB. If you
are a foreign insurer, check the box and, if you are entitled to a tax
reduction, attach a completed Illinois Schedule INS, Tax for Foreign
Insurers. Combined unitary return lers with one or more foreign
insurer members, check both boxes and follow the instructions for
both boxes. If your unitary group is entitled to a tax reduction, attach
a completed Illinois Schedule UB/INS, Tax for a Unitary Business
Group with Foreign Insurer Members.
See the specic instructions for Step 8 in order to claim the
tax reduction calculated on Schedule INS or Schedule UB/INS.
D — Check the box if you are ling this form only to report an
increased net loss, you have no surcharges for Compassionate
Use of Medical Cannabis Program Act or sale of assets by gaming
licensee on your original or amended return, and no overpayment
will result. Complete Steps 2 and 3, Step 4, if applicable, and Step 5,
Lines 35 through 37. Sign the return in Step 9 and leave the rest of
the form blank.
E — If you completed federal Form 8886 or federal Schedule M-3,
Part II, Line 12, to report a tax shelter and you did not attach a copy
to the original return, check the appropriate box and attach a copy
of the federal form or schedule to this return. If you are ling this
return because of changes associated with federal Form 8886 or
federal Schedule M-3, Part II, Line 12, provide a detailed explanation
in the “Explain the changes on this return” area.
F — If you are a unitary company and completed Schedule UB,
check the box and attach Schedule UB to your return.
G — If you are a unitary company and completed Subgroup
Schedule, check this box and attach Subgroup Schedule. See
Subgroup Schedule Instructions for more information.
H —You must check the box and attach Schedule 1299-D, Income
Tax Credits (for corporations and duciaries), and any other required
support listed on Schedule 1299-D if you are entitled to take income
tax credits on Step 7, Line 48, of your Form IL-1120-X, even if the
amount is not changing from your original return, or if you have
earned credits in this tax year, but are unable to use them.
I — You must check the box and attach Form IL-4562, Special
Depreciation, if you are claiming special depreciation addition or
subtraction modications on Form IL-1120-X, even if the amounts are
not changing from your original return.
J — You must check the box and attach Schedule M, Other
Additions and Subtractions (for businesses), if you are claiming other
addition or subtraction modications on Form IL-1120-X, even if the
amounts are not changing from your original return.
K — You must check the box and attach Schedule 80/20,
Related-Party Expenses, if you are claiming related-party expense
modications on your Form IL-1120-X, even if the amounts are not
changing from your original return.
L — Check this box if you are a 52/53 week ler. A 52/53 week
ler is a scal ler with a tax year that varies from 52 to 53 weeks
because their tax year ends on the same day of the week instead of
the last day of the month.
M — Enter your entire federal employer identication number (FEIN).
If you are a unitary company, enter the FEIN of the designated agent.
N — Enter your North American Industry Classication System
(NAICS) Code. If you are unsure of your code, you can research the
information at www.census.gov/naics or www.irs.gov.
O— Enter your Illinois corporate le (charter) number assigned to
you by the Illinois Secretary of State. If you are ling a unitary return,
enter the corporate le (charter) number of the designated agent.
P — Check the appropriate box for the reason you are ling
this return. If you are amending due to a federal change, you
must check the appropriate box for partial agreed or nalized and
include the date of IRS nalization, which might not be the date the
federal amended return was led. Attach a dated copy of any federal
examining ocer’s report. If you do not provide this date or the
required attachments, you may be assessed penalties and interest.
Q — If you are ling Form IL-1120-X on or before the extended due
date, and wish to make the election to treat all income, other than
compensation, as business income for this tax year, check this box.
If you previously had nonbusiness income on Form IL-1120, Step
4, Lines 24 and 32, you must reduce these amounts to zero on this
Form IL-1120-X. Once made, the election is irrevocable. If you are
ling Form IL-1120-X after the extended due date of the original
return and did not make the election on your original return, you
cannot check this box.
R — Check the box if you must adjust your loss or loss carryover
due to Discharge of Indebtedness. For more information, see the
instructions for Line 36 and Schedule NLD or UB/NLD Instructions.
S — Check the box if you are a cooperative and completed
Schedule INL either to make a rst-time election for treatment of
income or to gure your patronage and nonpatronage income or loss,
or you are a real estate mortgage investment conduit (REMIC) that
completed Schedule INL to make an adjustment to Illinois income.
Attach Schedule INL to your tax return.
T — Check this box if you annualized your income on
Form IL-2220, Computation of Penalties for Businesses. Attach
Form IL-2220 to your tax return. If you are ling Form IL-1120-X after
the extended due date of the original return, you cannot check this
box. Late-payment penalty for underpayment of estimated tax is
based on the tax shown due on your original return.
U — Check this box only if you have sales into Illinois and you
are not required to allocate them because you are protected by
Public Law 86-272. Complete Steps 1 through 5 of Form IL-1120-X.
V — Check this box if you are ling this amended return to report
changes to your Illinois sales factor numerator due to the inclusion or
exclusion of throwback sales.
W — Check this box if you are ling this amended return to report
changes to your Illinois sales factor numerator due to the inclusion or
exclusion of double throwback sales.
Explain the changes on this return
The purpose of this area is to allow you to explain what specic
changes you are making to your Illinois tax return. You should
include all relevant information, including, but not limited to, changes
made to
• specic addition and subtraction modications,
• unitary membership or unitary status,
• the business income election,
Specic Instructions
Page 4 of 6
IL-1120-X Instructions (R-12/23)
• credit or credit recapture amounts,
• the Illinois net operating loss deduction, and
• the federal or other state return that caused changes to the
Illinois return.
You must provide an explanation for each line item you change.
If your changes generate an overpayment which you elect to receive
as a credit carryforward and you elect to apply that credit to a tax
year other than the year described in the Line 66 instructions, you
must follow the instructions found under “May I apply my credit to a
dierent tax year?” If you fail to include the required information in
your explanation, your election will be considered invalid and we will
not apply your credit as you requested.
General Information for Steps 2 through 7
Column A — Enter the amounts from your most recently led or
adjusted return for the year that you are amending. These may be
gures from your original Form IL-1120, or a previously amended or
audited return.
Column B — Enter the correct amount for each line in Column B.
For each line item you change, you must provide an explanation for
that change in the “Explain the changes on this return” area.
If you are ling this form only to report an increase in your
Illinois net loss, you have no surcharges for Compassionate Use of
Medical Cannabis Program Act or sale of assets by gaming licensee
on your original or amended return, and the change will not result in
an overpayment, see the instructions for Step 5, Line 35.
Step 2: Figure your income or loss
Lines 1 through 8 — Refer to your Form IL-1120, Step 2, Specic
Instructions, for the year being amended.
Do not apply your Illinois net loss deduction amount in this
step. Net Loss Deductions (NLDs) are reported on Step 5, Line 38.
Step 3: Figure your base income or loss
Lines 10 through 22 — List each item and the amount on the line
provided. You must identify all subtractions and attach all of the
required supporting documentation.
Line 23 — This is your base income or loss.
Column A — Enter the amounts from your most recently led or
adjusted return. Do not check a box on Lines A or B to indicate
how your income was reported on your most recently led or
adjusted return. The check boxes on Lines A and B are used when
reporting your amended base income or loss in column B.
Column B — Follow the instructions on the form and check the box
on Line A or B that applies to the amount in Column B. You must
check one of these boxes and follow the instructions for that line
when completing Column B.
Check the box on Line A if
• all of your base income or loss is derived inside Illinois; and
• you do not have any income or loss to report on Lines 24, 25,
32, or 33.
If you check the box on Line A, do not complete Step 4,
Column B. All of your amended base income or loss is allocable
to Illinois. Skip Step 4, Column B, enter the amount from Step 3,
Column B, Line 23 on Step 5, Column B, Line 35, and complete the
remainder of the return.
Check the box on Line B if any of the following apply:
• your base income or loss is derived inside and outside Illinois;
• all of your base income or loss is derived outside Illinois; or
• you have income or loss to report on Lines 24, 25, 32, or 33.
If you check the box on Line B, you must complete all lines of
Step 4, Column B. Submitting Form IL-1120-X with an incomplete
Step 4, Column B, including Lines 28, 29, and 30 may result in a
delay in processing your return, further correspondence, and you
may be required to submit further information to support your ling.
See the the specic instructions for Step 4 for more information.
Unitary lers - You must complete both Step 4 of the
Schedule UB and Step 4, Column B of the Form IL-1120-X.
Step 4: Figure your income allocable to Illinois
Complete Step 4 only if you originally completed this part, or
you need to make a change that aects your base income or
loss allocable to Illinois. Refer to Form IL-1120, Step 4, Specic
Instructions, for the year being amended.
You must check the box on Line B and complete Step 4 if any
portion of Column B, Line 23, base income or loss, is derived outside
Illinois, or you have any income or loss to report on Column B, Lines
24, 25, 32, or 33.
If you do not complete all of Step 4, Column B, Lines 24 through 34,
we may issue a notice and demand proposing 100 percent of income
as being allocated to Illinois, or in the case of a loss return, a notice
indicating none of your loss as being allocated to Illinois.
Lines 24 and 32 — If you elected to treat all of your income other
than compensation as business income on your original tax return,
you must follow that election by entering zero on Form IL-1120-X,
Lines 24 and 32, if it is after the extended due date of the return.
If you are ling Form IL-1120-X before the extended due date and
are making the election to treat all nonbusiness income as business
income, Column B, Lines 24 and 32 should be reduced to zero.
Step 5: Figure your net income
Line 35 — Follow the instructions on the form. If the amount in
Column A reects income and the corrected amount in Column B
reects a loss, you may be able to carry this loss to other years as an
Illinois NLD. See the Net Loss Deduction information and Schedule
NLD or UB/NLD Instructions for more information.
If you are ling this form only to report an increase in your
Illinois net loss, you have no surcharges for Compassionate Use of
Medical Cannabis Program Act or sale of assets by gaming licensee
on your original or amended return, and the change will not result in
an overpayment, check the box in Step 1, Line D, complete Steps 2
and 3, Step 4, if applicable, and Step 5, Lines 35 through 37. Explain
what caused the increase in the Illinois net loss in the “Explain the
changes on this return” area and sign the return in Step 9. Leave the
rest of the form blank.
Line 36 — If you were required to reduce the net operating loss
reported on your U.S. Form 1120 because you excluded any
discharge of indebtedness income from this tax year’s gross income,
then you may be required to reduce the net loss reported on Line 35.
Use the Loss Reduction Worksheet of the IL-1120 Instructions to
gure your loss reduction. Attach a copy of your federal Form 982,
Reduction of Tax Attributes Due to Discharge of Indebtedness,
and a detailed statement to your Form IL-1120-X. For more
information, see 86 Ill. Adm. Code Section 100.2310(c).
If you are a combined group reporting a combined net loss on
Line 35, you may be required to reduce this loss if one or more of
your group members excluded discharge of indebtedness income
and was required to reduce a federal net operating loss incurred for
this tax year.
If you also have Illinois net operating loss carryovers to
the tax year of the debt cancellation, you may also be required to
reduce those carryovers. See Schedule NLD Instructions for more
information.
Page 5 of 6
IL-1120-X Instructions (R-12/23)
Line 37 — If you have a discharge of indebtedness adjustment
on Line 36, add Lines 35 (a negative number) and 36 (a positive
number), and enter the result here. This amount cannot be greater
than zero.
If you do not have a discharge of indebtedness adjustment,
enter zero on Line 36 and enter the amount from Line 35 on Line 37.
Line 38 — Enter your Illinois net loss deduction carryforward
from Illinois Schedule NLD, Step 1, Line 7 total box, or Illinois
Schedule UB/NLD, Step 3, Line 30. Attach Illinois Schedule NLD or
Unitary Illinois Schedule UB/NLD to your Form IL-1120-X.
For tax years ending on or after December 31, 2021, and
before December 31, 2024, this amount is limited to $100,000 or
less.
If you are a cooperative and you separate your patronage and
nonpatronage income or loss, complete Schedule INL and follow
the directions for computation of your Illinois net loss deduction in
Schedule NLD or Schedule UB/NLD Instructions.
If any of the loss being claimed on Line 38, originated from a
company other than the one ling this return, check the box on
Line 38 and attach a detailed statement to your return with
• the FEIN of the company from which you acquired the loss,
• the reason (e.g., merger) you are allowed to use that company’s
losses, and
• the date you acquired the loss.
Step 6: Figure your replacement tax after credits
Follow the instructions on the form. Be sure to attach any required
schedules or forms.
Line 41 — See Illinois Schedule 4255, Recapture of Investment Tax
Credits, for more information. You must attach Illinois Schedule 4255
if you have an amount on this line.
Line 43 — See Form IL-477, Replacement Tax Investment Credits,
for more information. You must attach Form IL-477 and any other
required support listed on Form IL-477 if you have an amount on this
line.
Step 7: Figure your income tax after credits
Follow the instructions on the form and attach any required
schedules.
Line 45 — See Form IL-1120, Line 45 instructions for the amount to
enter here.
Line 46 — See Illinois Schedule 4255 for more information regarding
the recapture of investment credits. You must attach Illinois
Schedule 4255 if you have an amount on this line.
Line 48 — See Illinois Schedules 1299-D and 1299-I for more
information regarding income tax credits. If you have an amount on
this line, check the box in Step 1, Line H, and attach Illinois Schedule
1299-D and any other required support listed on Schedule 1299-D.
Step 8: Figure your refund or balance due
If you are ling this form only to report an increase in your
Illinois net loss, you have no surcharges for Compassionate Use of
Medical Cannabis Program Act or sale of assets by gaming licensee
on your original or amended return, and an overpayment will not
result, do not complete this step.
If you are a foreign insurer, review the instructions below.
For non-unitary foreign insurers
• complete Form IL-1120-X, Steps 1 through 7, before completing
Illinois Schedule INS;
• complete Schedule INS;
• report your foreign insurer replacement tax reduction on Step 8,
Line 51; and
• report your foreign insurer income tax reduction on Step 8,
Line 54.
For combined unitary lers with one or more members who are
foreign insurers
• complete Form IL-1120-X, Steps 1 through 7, before completing
Illinois Schedule UB/INS;
• complete all steps of your Schedule UB, before completing
Illinois Schedule UB/INS;
• complete Schedule UB/INS;
• report your foreign insurer replacement tax reduction on Step 8,
Line 51; and
• report your foreign insurer income tax reduction on Step 8,
Line 54.
Line 50 — Follow the instructions on the form.
If you are a foreign insurer do not apply a tax reduction
to this line. Follow the instructions above and on Schedule INS or
Schedule UB/INS.
Line 51 — Enter your foreign insurer replacement tax reduction from
Schedule INS, Step 3, Line 17, or Schedule UB/INS, Step 6, Line 60.
Attach Schedule INS or Schedule UB/INS.
Line 52 — Subtract Line 51 from Line 50 and enter the result on this
line. If Line 51 is blank, enter the amount from Line 50 on Line 52.
This is your net replacement tax.
Line 53 — Follow the instructions on the form.
If you are a foreign insurer do not apply a tax reduction
to this line. Follow the instructions above and on Schedule INS or
Schedule UB/INS.
Line 54 — Enter your foreign insurer income tax reduction from
Schedule INS, Step 3, Line 20, or Schedule UB/INS, Step 6, Line 73.
Attach Schedule INS or Schedule UB/INS.
Line 55 — Subtract Line 54 from Line 53 and enter the result on this
line. If Line 54 is blank, enter the amount from Line 53 on Line 55.
This is your net income tax.
Line 56 — Compassionate Use of Medical Cannabis Program Act
surcharge. Use the instructions and the Surcharge Worksheet in the
Form IL-1120 Instructions to gure your surcharge.
Line 57 — Sale of assets by gaming licensee surcharge. Use
the instructions and Surcharge Worksheet in the Form IL-1120
Instructions to gure your surcharge.
Line 58— Add Lines 52, 55, 56, and 57, and enter the total on
this line. This is your total net income and replacement taxes, and
surcharges.
Line 59a — Enter the sum of any overpayment from your prior year
tax returns that you requested to be applied to this year’s tax return.
Take into account any correspondence we may have sent that
changed the amount of your credit carryforward from the previous
year.
Line 59b — Enter the sum of the following, not including any penalty
and interest previously paid:
• estimated payments or tax prepayments made during the tax
year,
• extension payments,
• any tax payments you made with a previously led
Form IL-1120-X, and
• any other payments made prior to the date this amended return
is led (e.g., responding to a bill).
Line 59c — Enter the amount you wish to claim of Illinois
pass-through withholding (including any eligible investment
partnership withholding) payments reported to you by partnerships,
S corporations, or trusts, on Schedule(s) K-1-P or K-1-T. If you
received more than one Schedule K-1-P or K-1-T, add the amounts
from all the schedules and enter the total on Line 59c. Attach copies
of the Schedules K-1-P and K-1-T you received from the pass-
through entities to your Form IL-1120. See “What is pass-through
withholding and pass-through entity (PTE) tax?” under “General
Information” in the Form IL-1120 Instructions for more information.
Page 6 of 6
IL-1120-X Instructions (R-12/23)
Partners in an investment partnership may not be eligible to
claim a Schedule K-1-P, Step 7, Line 55 amount reported to them by
the investment partnership. See Schedule K-1-P(2) for information
about when a partner may claim investment partnership withholding
credit.
Line 59d — Enter the amount of any PTE tax credit received as
shown on Schedule(s) K-1-P and K-1-T. Attach Schedule(s) K-1-P
and K-1-T.
Line 59e — Enter the amount of any Illinois gambling withholding
and withholding from sports wagering winnings shown on
Form W-2G. Attach Forms W-2G.
Line 61 — Enter previously paid penalty and interest. This
information can be obtained from your MyTax Illinois account. Sign
into mytax.illinois.gov to view your account or to register for an
account.
Line 62 — Enter the total amount of any overpayment, credit
carryforward, or refund (whether or not you received the
overpayment) reported on your previously led Form IL-1120 or
Form IL-1120-X. Do not include interest that you received. Do
not reduce the amount reported on this line to pay a tax increase
reported on an amended return led after the extended due date of
the original return. You cannot change the amount to be credited
forward from the amount reported on your original return after the
extended due date.
Line 66 — Enter the amount of overpayment you elect to be applied
against your estimated tax obligation. Check the box on this line
if this is your nal return and any remaining carryforward is being
transferred to another entity. Attach a detailed statement to your
return listing the FEIN of the entity receiving the credit carryforward,
the date the credit was transferred, and the reason for the transfer.
See Form IL-1120, Step 8, Line 64 instructions for more information.
Your credit carryforward will not be applied if you do not le a
processable return.
If your overpayment accrues interest and you elect to receive your
• entire overpayment as a credit carryforward, any interest
due will be applied with your credit as an additional credit
carryforward. We will calculate the amount of interest due
and notify you. When you claim your credit carryforward in a
future year you must include this interest amount in the amount
claimed.
• overpayment as both a credit carryforward and a refund, we
will apply the credit as you request and include any interest due
with your refund.
Your credit carryforward may be reduced by us due to
corrections we make to your return, or to satisfy any unpaid tax,
penalty, and interest due for this year or any other year. If we reduce
your credit carryforward, it may result in a late-payment penalty in a
subsequent year.
May I apply my credit to a dierent tax year?
Yes. If you wish to apply your credit to a tax year other than the one
described above, you must indicate the tax year to which you wish to
have the credit apply in the “Explain the changes on this return” area.
If you do not follow these instructions, your election will be
considered invalid and we will apply your credit as indicated under
“To which tax year will my credit apply?” in the Form IL-1120
Instructions.
If you submit a valid request, we will apply your credit as you
requested and notify you. Once made, your election to change the
tax year to which your credit will apply is irrevocable.
You may only apply your credit to tax years occurring after
the year of the return creating the overpayment. If you request to
apply more credit than our records show you have available, we
will apply the maximum amount available and notify you of the
dierence.
Line 67 — Follow the instructions on the form. We will calculate any
interest that may be due you and include it in your refund check. Any
refund may be reduced to satisfy any outstanding liability.
We do not currently oer direct deposit as a method for receiving a
refund from an amended return. Overpayments will be refunded by
check.
Line 68 — Follow the instructions on the form. This is your amount
of tax due that must be paid in full if $1 or more. We encourage you
to let us gure your penalties and interest and send you a bill instead
of determining these amounts yourself. We will compute any penalty
and interest due and notify you. For more information see “What
are the penalties and interest?” and Publication 103, Penalties and
Interest for Illinois Taxes.
We will apply all payments against tax rst, penalty second,
and interest third.
If you have a balance due on Line 68 be sure to enter the amount
you are paying on the top of Page 1 of Form IL-1120-X. Complete
Form IL-1120-X-V, Payment Voucher for Amended Corporation
Income and Replacement Tax, make your check or money order
payable to “Illinois Department of Revenue”, and attach them both
to the front of the return or le and pay electronically.
Step 9 — Signature, date, and paid preparer’s
information
You must sign and date your return. If you do not sign your return,
it will not be considered led and you may be subject to a nonler
penalty.
If you pay someone to prepare your return, the income tax return
preparer must also sign and date the return, enter the preparer tax
identication number (PTIN) issued to them by the Internal Revenue
Service, and provide their rm’s name, FEIN, address, and phone
number.
If you want to allow the paid preparer listed in this step to discuss
this return with IDOR, check the box. This authorization will allow
your paid preparer to answer any questions that arise during the
processing of your return, call us with questions about your return,
and receive or respond to notices we send. The authorization will
automatically end no later than one year after you le your amended
return. You may revoke the authorization at any time by calling or
writing us.
