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Business or Farm Income Apportionment Formula (IAF) Worksheet

You must complete this worksheet if you received business or farm income from both inside and outside of Illinois. If you have more than one source of business or farm income, make copies of this worksheet and prepare a separate worksheet for each line of the Schedule CR on which you reported business or farm income.

Worksheet for Schedule CR, Line:

Column A
Total sales everywhere

Column B
Total sales in Illinois

Column C
Apportionment Factor
Column B ÷ Column A

1 Line 1 is 1.000000.

2 Figure your apportionment factor.

3 Subtract Line 2 from Line 1.

4 Enter the amount of your business or farm income from Schedule CR, Column A.

5 Apportioned Income – Multiply Line 4 by the Line 3 decimal. Enter the result here and on the corresponding line on Schedule CR, Column B.

Keep a copy of this worksheet with your income tax records.

IAF Worksheet Instructions

Line 1:

Line 1 must be 1.000000.

Line 2: Apportionment factor

Column A

Enter the total amount of sales you received from both inside and outside Illinois.

Column B

Enter the total amount of sales you received in Illinois.

Column C

Divide Column B by Column A. Carry the decimal to six places. This is your apportionment factor.

Lines 3 through 5:

Follow the instructions on the worksheet.

Note: If you need more detailed instructions, see the instructions for Form IL-1120, Corporation Income and Replacement Tax Return, Step 4. If your business income was derived from a transportation company, an insurance company, or a financial organization, see Form IL-1120 Specific Instructions for “Apportionment Formulas.”