The following changes are effective for the tax year beginning January 1, 2018, and will be reflected on the 2018 Missouri Individual Income Tax Returns.

Due Date

The due date for the 2018 Missouri Individual Income Tax Return is April 15, 2019.

Tax Rate Changes-Indexed for Inflation

    If the Missouri taxable income is...
    The tax is...
    $0 to $102 $0
    At least $103 but not over $1,028 1-1/2% of the Missouri taxable income
    Over $1,028 but not over $2,056 $15 plus 2% of excess over $1,028
    Over $2,056 but not over $3,084 $36 plus 2-1/2% of excess over $2,056
    Over $3,084 but not over $4,113 $62 plus 3% of excess over $3,084
    Over $4,113 but not over $5,141 $93 plus 3-1/2% of excess over $4,113
    Over $5,141 but not over $6,169 $129 plus 4% of excess over $5,141
    Over $6,169 but not over $7,197 $170 plus 4-1/2% of excess over $6,169
    Over $7,197 but not over $8,225 $216 plus 5% of excess over $7,197
    Over $8,225 but not over $9,253 $267 plus 5-1/2% of excess over $8,225
    Over $9,253 $324 plus 5.9% of excess over $9,253


Personal Exemption (HB 2540 - 2018 Session)  

Due to the changes in Federal Law, the Missouri exemption amounts are zero and were removed from the 2018 Missouri return(s). These include:

  • Personal exemption
  • Dependent exemption (including stillborn)
  • Additional personal exemption
  • Over age 65 dependent exemption

Federal income tax changes affecting the Missouri return

Missouri individual income tax follows certain amounts set by the Internal Revenue Services. Below are the standard deduction amounts that changed for the tax year 2018:

  • Single - $12,000
  • Married filing combined - $24,000
  • Married filing separate - $12,000
  • Head of Household - $18,000
  • Qualified Widow(er) - $24,000

The 2018 Federal return (Form 1040) was changed, and now includes additional supporting schedules (Schedules 1 though 6). Line number references for the federal return can be found on these schedules. (Example: Line 45 is the Alternative Minimum Tax, and can be found on Schedule 2.)

Itemized Deduction

Missouri requires taxpayers to remove the same income tax deduction from the federal itemized deduction to compute the Missouri itemized deduction. Starting with the 2018 tax year, there is no longer an overall limitation of federal itemized deduction. However, the state tax deduction portion of federal itemized deduction is limited to $5,000 for married filing separately, and $10,000 for all other taxpayers (single, married filing combined, and head of household).

Taxpayers with state deduction greater than the $5,000 or $10,000 threshold amounts should complete the Net State Income Taxes worksheet located beneath the Missouri Itemized Deductions schedule of your tax return.

Business Income Deduction

Beginning with the 2018 tax year, a deduction is allowed of 5% of "business income", which will be the combination of amounts reported on Schedule C and Schedule E of the federal income tax return. To assist with calculating the deduction amount, please complete the worksheet located on page 42 of the Form MO-1040 instructions. This deduction will be reported as a subtraction modification on the Form MO-A, Part 1 of your tax return.

Missouri's 529 Education Program (SB 882 - 2018 session)

Contributions to a Section 529 education savings plan have been allowed as a subtraction the Missouri return, with the requirement that distributions from the program be used for higher education expenses. In conjunction with federal changes to Section 529 of the Internal Revenue Code, Missouri allows these distributions to remain tax-free if they are used to pay elementary and secondary education expenses as well. More information about Missouri's 529 saving plan is available at