Schedule M (IL-1120, IL-1120-ST, IL-1065, IL-1041): Other Additions and Subtractions (for businesses) (2024)

Illinois · Illinois DOR · Used for tax years 2024

Illinois Schedule M reports other additions and subtractions for businesses, trusts, and estates. It calculates totals to enter on Form IL-1120, IL-1120-ST, IL-1065, or IL-1041 and is attached to that return.

Who files this form

Schedule M reports other additions and subtractions for businesses filing Form IL-1120, IL-1120-ST, IL-1065, or IL-1041. Attach it to the applicable return.

The 2024 schedule is for tax years ending on or after December 31, 2024. Some lines apply only to specific return types, as marked on the form.

What you'll need

  • Your name as shown on your tax return, federal employer identification number (FEIN), and tax year ending month and year.
  • Amounts for the additions and subtractions that apply to you.
  • If claiming interest on qualifying Illinois state or local government obligations on Line 20, a copy of the statement identifying the payer and the interest amount for each obligation. Attach this statement.
  • If claiming unused patronage or nonpatronage losses on Line 34, the amounts from Schedule INL and the year you first made the Schedule INL, Step 2, Line 1a election.

How to file

Attach Schedule M to your Form IL-1120, IL-1120-ST, IL-1065, or IL-1041. The supplied form does not give a mailing address or e-filing directions.

  1. Complete Step 1 with your name and FEIN, and enter your tax year ending month and year.
  2. Complete the applicable additions in Step 2. Add Lines 1 through 10 and enter the total on Line 11.
  3. Complete the applicable subtractions in Step 3, carrying the totals forward as directed. Enter total subtractions on Line 40.
  4. Transfer the totals to your return:
  • IL-1120: additions to Line 8; subtractions to Line 21.
  • IL-1120-ST: additions to Line 21; subtractions to Line 33.
  • IL-1065: additions to Line 22; subtractions to Line 33.
  • IL-1041: additions to Line 10; subtractions to Line 24.

Common mistakes

  • Entering an unapproved subtraction on Line 39. Do not enter an amount unless instructed by the Illinois Department of Revenue (IDOR). An unapproved subtraction may delay processing.
  • Leaving out required information. The form warns that disclosure is required and failure to provide information could result in a penalty.

Questions people ask

Can every filer use every line?

No. Some lines are restricted to particular return types. For example, Lines 5 and 6 are for IL-1041 filers only, and Line 9 is for IL-1120 filers only.

Can I subtract all Illinois state and local government bond interest?

Line 20 lists the qualifying obligations and applies only if the interest was included in Illinois income. Attach a statement identifying the payer and interest amount for each obligation.

Where do I report other additions?

Use Line 10 and identify each item.

Can I use Line 39 for a subtraction not listed elsewhere?

Only if IDOR instructs you to do so. Line 39 is for eligible Publication 101 subtractions not taken anywhere else, and you must identify each item.

Official sources

All versions of Schedule M (IL-1120, IL-1120-ST, IL-1065, IL-1041)