Form MO-1040 at a glance
What it is: Form MO-1040 is the 2025 Individual Income Tax Return - Long Form for Calendar Year January 1 - December 31, 2025.
Who signs: Spouse's Signature (If filing combined, BOTH must sign).
A filled-in Form MO-1040 example: a single filer who is 65 or older
How to fill out Form MO-1040, box by box
Filing Status
Filing Status: Single, Claimed as a Dependent, Married Filing Combined, Married Filing Separately, Head of Household or Qualifying Widow(er).
Age, Blind, 100% Disabled and Non-Obligated Spouse
Age 62 through 64, Age 65 or Older, Blind, 100% Disabled and Non-Obligated Spouse, each for Yourself or Spouse.
Yourself or Spouse: Deceased in 2025.
Your Social Security Number and name
Enter your Social Security Number, First Name, M.I., Last Name and Suffix.
Your Spouse's Social Security Number and name
Spouse's Last Name, Spouse's First Name, M.I. and Suffix, with the Spouse's Social Security Number.
Present Address and County of Residence
Enter the Present Address (Include Apartment Number or Rural Route), City, Town, or Post Office, State, ZIP Code and County of Residence.
More rules for Form MO-1040
Print in BLACK ink only and DO NOT STAPLE.
Enter the In Care Of Name (Attorney, Executor, Personal Representative, etc.).
Line 1: Federal adjusted gross income from federal return (see instructions and worksheet on pages 6 and 7), for Yourself (Y) and Spouse (S).
Line 2: Total additions (from Form MO-A, Part 1, Line 7). Line 3: Total income - Add Lines 1 and 2. Line 4: Total subtractions (from Form MO-A, Part 1, Line 19). Line 5: Missouri adjusted gross income - Subtract Line 4 from Line 3.
Line 6: Total Missouri adjusted gross income - Add columns 5Y and 5S. Line 7: Income percentages - Divide columns 5Y and 5S by total on Line 6. (Must equal 100%)
Line 8: Pension, Social Security and Social Security Disability exemption (from Form MO-A, Part 3, Section D).
Line 11: Total tax from federal return. Do not enter federal income tax withheld.
Line 12: Federal tax percentage - Enter the percentage based on your Missouri Adjusted Gross Income, Line 6, from the chart: $25,000 or less 35%, $25,001 to $50,000 25%, $50,001 to $100,000 15%, $100,001 to $125,000 5%, $125,001 or more 0% (checked November 3, 2026).
Line 13: Federal income tax deduction - Multiply Line 11 by the percentage on Line 12. Enter this amount not to exceed $5,000 for an individual or $10,000 for combined filers (checked November 3, 2026).
Line 14: Missouri standard deduction or itemized deductions (If itemizing, See Form MO-A, Part 2): Single or Married Filing Separate-$15,750; Head of Household-$23,625; Married Filing Combined or Qualifying Widow(er)-$31,500 (checked November 3, 2026).
Line 24: Foster parent tax deduction. Line 25: Total deductions - Add Lines 8 and 13 through 24. Line 26: Subtotal - Subtract Line 25 from Line 6.
Line 27: Multiply Line 26 by appropriate percentages (%) on Lines 7Y and 7S. Line 28: Enterprise zone or rural empowerment zone income modification. Line 29: Taxable income - Subtract Line 28 from Line 27.
Line 30: Tax (see tax chart on page 21 of the instructions).
Line 32: Missouri income percentage - Enter 100% if not completing Form MO-NRI. Line 33: Balance - Subtract Line 31 from Line 30; OR multiply Line 30 by percentage on Line 32. Line 35: Subtotal - Add Lines 33 and 34. Line 36: Total Tax - Add Lines 35Y and 35S.
Line 37: MISSOURI tax withheld - Attach Forms W-2 and 1099. Line 38: 2025 Missouri estimated tax payments - Include overpayment from 2024 applied to 2025.
Line 43: Property tax credit - Attach Form MO-PTS. Line 45: Total payments and credits - Add Lines 37 through 44.
Line 49: If Line 45, or if amended return, Line 48, is larger than Line 36, enter the difference. Line 50: Amount of Line 49 to be applied to your 2026 estimated tax.
Line 53: REFUND - Subtract Lines 50, 51, and 52 from Line 49 and enter here.
Line 54: If Line 36 is larger than Line 45 or Line 48, enter the difference. Line 55: Underpayment of estimated tax penalty - Attach Form MO-2210. Enter penalty amount here. Select this box if you are a farmer exempt from the underpayment of estimated tax penalty. Line 56: AMOUNT DUE - Add Lines 54 and 55.
If you pay by check, you authorize the Department of Revenue to process the check electronically. Any returned check may be presented again electronically.
Enter your E-mail Address and Daytime Telephone.
Declaration of preparer (other than taxpayer) is based on all information of which he or she has knowledge. The preparer enters the Preparer's Signature, Date (MM/DD/YY), Preparer's FEIN, SSN, or PTIN, Preparer's Telephone and Preparer's Address.
If your situation is different
You are filing an amended return
Amended Return.
Skip Lines 46 through 48 if you are not filing an amended return.
Enter the Amount paid on original return on Line 46 and the Overpayment as shown (or adjusted) on original return on Line 47; Line 48, Amended return total payments and credits, is Add Lines 45 and 46; subtract Line 47.
Indicate Reason for Amending: A. Federal audit, B. Net Operating Loss carryback, C. Investment tax credit carryback, or D. Correction other than A, B, or C. Enter date of federal amended return, if filed.
Composite Return
Composite Return (For use by S corporations or Partnerships).
If filing a fiscal year return
If filing a fiscal year return, enter the beginning and ending dates here.
Federal Extension
If you have an approved federal extension, select Federal Extension and attach a copy of Federal Extension (Form 4868).
Did you pay a tax return preparer to complete your return, but the preparer failed to sign the return?
Did you pay a tax return preparer to complete your return, but the preparer failed to sign the return or provide an Internal Revenue Service preparer tax identification number? If you marked yes, insert the preparer's name, address, and phone number in the applicable sections of the signature block.
Common questions about Form MO-1040
Who signs it?
Sign and enter the Date (MM/DD/YY) under Signature, and enter the Date (MM/DD/YY) for the Spouse's Signature.
Is there a penalty?
As provided in Chapter 143, RSMo., a penalty of up to $500 shall be imposed on any individual who files a frivolous return (checked November 3, 2026).
What am I certifying when I sign?
Under penalties of perjury, I declare that I have examined this return, including accompanying schedules and statements, and to the best of my knowledge and belief it is true, correct, and complete. By signing or entering my name in the "Signature" field(s) below, I am providing the Department of Revenue with my signature as required under Section 143.561, RSMo. I also declare under penalties of perjury that I employ no illegal or unauthorized aliens as defined under federal law and that I am not eligible for any tax exemption, credit, or abatement if I employ such aliens. I am aware of any applicable reporting requirements of Section 135.805, RSMo, and the penalty provisions of Section 135.810, RSMo.
Sources
[1] Form MO-1040 (Revised 12-2025), 2025 Individual Income Tax Return - Long Form, Missouri Department of Revenue (the Official source link on this page).