Missouri Income Tax Elimination: Rate, Triggers, and Amendment 5

Missouri is phasing out its individual income tax through automatic rate cuts written into state law, and voters will decide in August 2026 whether to lock full elimination into the state constitution. The Missouri income tax elimination plan works through revenue triggers: each time general revenue grows enough over the prior three years, the top rate drops another tenth of a percentage point. For the 2026 tax year, the top rate sits at 4.7%, down from 5.3% in 2022. There is no fixed end date. The pace depends on how quickly the state’s economy grows.

Where the Top Rate Stands for 2026

The framework lives in Missouri Revised Statutes Section 143.011, rewritten during the 2022 special session when lawmakers passed Senate Bill 3. That bill cut the top rate from 5.3% to 4.95% starting January 1, 2023, eliminated the lowest tax bracket entirely, and set up a schedule for further reductions tied to revenue performance.¹²

Since then, Missouri has hit its revenue benchmarks two years running. The top rate dropped to 4.8% for 2024, then to 4.7% for 2025, and it stays at 4.7% for 2026, applying to taxable income above $9,436.³ Income under $1,348 is not taxed at all. Between those figures, a graduated schedule applies:

$0 to $1,348: 0%
$1,348 to $2,696: 2%
$2,696 to $4,044: 2.5%
$4,044 to $5,392: 3%
$5,392 to $6,740: 3.5%
$6,740 to $8,088: 4%
$8,088 to $9,436: 4.5%
Over $9,436: 4.7%

Under the statute, each bracket at the top rate gets absorbed as the rate falls below it. Once the top rate drops below 4.5%, the bracket structure compresses further, and Missouri moves toward a flat tax on income above the zero-bracket threshold, and then toward no tax at all.¹

The Revenue Triggers That Control the Pace

None of these cuts happen on autopilot. Each one requires Missouri to actually collect enough money to absorb the reduction, and the law uses two different thresholds depending on where the rate stands.

The first trigger applied to the initial 0.15 percentage point cut that took effect in 2024. For that reduction, net general revenue in the prior fiscal year had to exceed the highest collection total from the previous three fiscal years by at least $175 million.¹ Every subsequent cut of 0.1 percentage point requires net general revenue to exceed the highest of the three prior fiscal years by at least $200 million. Only one reduction can happen per calendar year. If revenue growth falls short, the cut simply doesn’t happen that year, and the rate freezes where it last landed.

This design means Missouri will not slash its income tax during a downturn. Full elimination could take a decade or more if the economy slows, or arrive faster during sustained growth. The determination runs on audited fiscal year data, not projections, so the answer to “when will the tax hit zero” is genuinely unknown.

Amendment 5 on the August 2026 Ballot

The biggest open question is whether voters will change the rules. House Joint Resolutions 173 and 174 passed the Missouri House 95–59 and the Senate 18–11 on April 21, 2026, sending a constitutional measure to the ballot as Amendment 5 for the August 4, 2026 election.⁴

If it passes, Amendment 5 would do two things. First, it would require the legislature to keep reducing the top rate based on revenue growth until the income tax is fully gone, and then permanently bar the state from reimposing it. Second, it would lift an existing constitutional restriction that prevents the legislature from applying sales and use taxes to services. Missouri’s constitution currently bars expanding the sales tax base beyond what was taxed as of January 1, 2015. Amendment 5 would carve out an exception: lawmakers could tax currently untaxed services, such as haircuts, home repairs, and professional services, but only if they simultaneously cut the income tax by a dollar amount at least equal to the new sales tax revenue.⁴

Local governments would also be affected. Within twelve months of any sales tax base expansion, political subdivisions that impose a sales or use tax would have to make a one-time reduction to their sales tax rate, property tax levy, or both, cutting revenue by an amount equal to 97% of the additional revenue from the broader tax base.

Critics argue that replacing income tax revenue entirely through sales taxes would require taxing more than $300 billion in currently untaxed transactions and could shift more of the burden to lower-income households, who spend a larger share of their income on goods and services. Supporters say eliminating the income tax would make Missouri more competitive for businesses and workers. The individual income tax currently produces roughly $5 billion a year, about 31% of Missouri’s state-sourced revenue.

Retirement Income Is Already Exempt

One group has already crossed the finish line. Starting with the 2024 tax year, Missouri fully exempts Social Security benefits from state income tax. Under RSMo Section 143.125, any taxpayer age 62 or older can subtract 100% of their Social Security benefits from Missouri adjusted gross income, regardless of filing status or total income.⁵ Social Security disability benefits are also fully exempt at any age. Before 2024, higher-income retirees still owed state tax on part of their benefits.⁶

Missouri also offers a public pension subtraction. Retirees receiving benefits from a federal, state, or local government pension plan can subtract those benefits up to the maximum Social Security benefit for that year. For 2026, the maximum monthly benefit at full retirement age is $4,152, putting the annual cap at roughly $49,824.⁷ The pension subtraction is reduced dollar-for-dollar by any Social Security subtraction the taxpayer claims, so you cannot claim the full amount of both.⁸

Local Earnings Taxes Are Not Affected

If you work or live in Kansas City or St. Louis, the elimination plan does not touch your 1% local earnings tax. Both cities impose the tax on everyone who works or lives within city limits, and it is completely separate from the state income tax under RSMo 143.011.⁹ Kansas City’s earnings tax applies to all income earned by residents regardless of where they work, and to income earned within city limits by nonresidents.¹⁰ Even if the state rate eventually reaches zero, workers in these two cities will still see 1% withheld. Eliminating those local taxes would require separate action at the city level.

Filing While the Rate Falls

The obligation to file a Missouri return does not disappear just because rates are dropping. Residents still need to file if they are required to file a federal return and their Missouri adjusted gross income exceeds $1,200. Nonresidents with Missouri income above $600 also must file. If your Missouri adjusted gross income falls below your standard deduction plus your personal exemption, you can skip the state return.¹¹

For the 2026 tax year, Missouri’s standard deduction is $16,100 for single filers, $32,200 for married couples filing jointly where one spouse doesn’t work, and $24,150 for head-of-household filers.¹² If Missouri tax was withheld from your paycheck but you owe nothing, you still need to file to get that money back. As the top rate keeps dropping, more taxpayers will find that their standard deduction wipes out state liability entirely. The filing requirement itself will not vanish until the legislature changes it or the tax actually reaches zero, whichever comes first.

1
Missouri Revisor of Statutes. Missouri Code 143.011 – Resident Individuals – Tax Rates – Rate Reductions, When
2
Missouri Senate. Sen. Tony Luetkemeyer’s Legislative Column for Sept. 23, 2022
3
Missouri Department of Revenue. 2025 Individual Income Tax Year Changes
4
Ballotpedia. Missouri Amendment 5, Income Tax Elimination and Sales Tax Changes Amendment (August 2026)
5
Missouri Revisor of Statutes. Missouri Code 143.125 – Social Security Benefits Subtraction
6
Missouri Department of Revenue. Pension Tax Year 2024 FAQs
7
Social Security Administration. What Is the Maximum Social Security Retirement Benefit
8
Missouri Department of Revenue. Pension FAQs
9
City of Kansas City. Tax FAQs
10
City of St. Louis. Business Earnings Tax Information
11
Missouri Department of Revenue. Individual Income Tax FAQs
12
Missouri Department of Revenue. 2026 Missouri Withholding Tax Formula