Amendment 4 would let one of eight congressional districts veto what the whole state votes for. Amendment 5 would trade the income tax for a broader sales tax on everyday goods and services. Both are on the August 4 ballot.
Citizen initiatives would need a majority in all 8 congressional districts. Amendments the legislature writes would still need only a statewide majority.
See the detailsPhasing out the income tax means taxing more of what you buy. Independent analysis finds most Missourians pay more, while the top 1% average a $40,000 cut.
See the detailsThe short version
Amendments 4 and 5 are on the August 4, 2026 primary ballot. You do not need to pick a party primary to vote on them — ask for the nonpartisan ballot and the amendments still appear.
Amendment 4
The Ballot-Rights Amendment
Changes what it takes for a citizen initiative to amend the constitution: a majority statewide and a majority in every one of Missouri's eight congressional districts. Amendments the legislature refers keep the current simple-majority rule.2,7
See how one district can block the stateAmendment 5
The Tax Shift Amendment
Requires the legislature to phase out the individual income tax and authorizes it to expand sales and use taxes onto goods and services not taxed today. The replacement rates are not in the amendment — lawmakers would set them afterward.3,7
See what it would cost your householdMissouri has adopted every constitutional amendment in its history by statewide majority. Amendment 4 would end that — but only for the amendments citizens write themselves.
Citizen-initiated constitutional amendments would need a majority in every one of Missouri's 8 congressional districts — not just a statewide majority.2,7
Amendments referred to the ballot by the legislature would still pass on a simple statewide majority. The higher bar applies only to measures citizens put forward.2,7
Every Missouri constitution and every constitutional amendment in state history has been adopted by statewide majority. This would be a first.9
One district out of eight — about 12% of the state's districts — could veto a measure the other seven districts approved overwhelmingly.9,2our view
Official title
Require Approval in Each Congressional District for Citizen-Initiated Constitutional Amendments and Add Provisions on Petition Fraud and Foreign Contributions Amendment
Shall the Missouri Constitution be amended to: Modify current requirements that a statewide majority of voters may approve initiative petitions to amend the constitution; Require a majority of voters in each congressional district to approve initiative petitions to amend the constitution; and Make available to each voter the full text of initiative petitions with their ballot?
Drag any district to change how it votes. The scenario starts with seven districts at 80% yes and one at 49% — a measure more than three quarters of the state supports.
St. Louis City & inner county
St. Louis suburbs
East-central Missouri
West-central Missouri
Kansas City
Northern Missouri
Southwest Missouri
Southeast Missouri & Ozarks
Today’s rule — statewide majority
76.1%yes
Under Amendment 4
FAILS
Blocked by the 7th District, even though 76.1% of Missourians voted yes.
This higher bar would apply only to amendments citizens put on the ballot. Amendments referred by the legislature would still pass on a simple statewide majority.
Missouri still has to fund schools, roads, and public safety. Amendment 5 does not shrink that bill — it changes who pays it, shifting the burden from people with high incomes toward people who spend most of what they earn.
Requires the General Assembly to phase out the individual income tax, and once eliminated, bars the state from ever levying one again.3,7
Removes existing constitutional limits on taxing goods and services, authorizing sales tax on things not taxed today — home and car repair, insurance, personal care, and other services.3,6
The amendment does not specify the replacement sales tax rates. Those would be written later by the legislature, after the constitutional change is locked in.3,7
Official title
Income Tax Elimination and Sales Tax Changes Amendment
Shall the Missouri Constitution be amended to: Require legislative phase-out of the individual state income tax based on revenue growth, and authorize the expansion of sales and use taxes; Curtail constitutional limits on taxing goods and services; and Require local tax rate cuts without reducing school funding if local sales tax revenue increases?
Move the slider to your household income to see the trade Amendment 5 makes: income tax you stop paying, sales tax you start paying.
$65,000
+$2,350
−$2,873
Your estimated net change
+$523per year
You would pay more overall under Amendment 5.
This is an illustration, not tax advice. It is calibrated so the $50,000–$80,000 band reproduces ITEP’s published finding of roughly $535 more per year4, and assumes a broadened sales tax base at an effective added rate of about 6.5% — the range needed to replace roughly a third of state general revenue.
Your real result depends on your spending, filing status, and which goods and services the legislature chooses to tax. Amendment 5 does not set those rates; it authorizes lawmakers to set them after the amendment passes.3,7
Meanwhile, the top 1%
−$40,000
average tax cut per year
Missouri’s highest earners receive an average cut of nearly $40,000 — because eliminating an income tax returns the most money to the people with the most income.4
Seniors and fixed incomes
+$365
average increase per senior household — $335 million statewide. Retirement income is often already exempt from income tax, so there is little to gain and a broader sales tax to pay.5
What supporters say
Tap any card to flip it. We quote the argument fairly, then respond with sources. Where the facts are genuinely contested, we say so rather than overclaim.
Questions
Supporters frame Amendment 4 as protecting Missouri from outside influence and giving rural areas a stronger voice, and Amendment 5 as letting Missourians keep more of their paycheck. Both framings emphasize a popular-sounding side effect while leaving out the operative change. Amendment 4's actual mechanism is a requirement that citizen initiatives win a majority in all eight congressional districts, which lets one district veto the other seven — a restriction that does not apply to amendments the legislature itself puts on the ballot. Amendment 5's actual mechanism is replacing income tax revenue with a broader, higher sales tax, which shifts who pays rather than reducing what is collected.2,3,7
Every answer above links to its sources in the citations list.
Take action
Turnout in an August primary is low, which means a small number of voters decides this. Your plan — and the three people you send this to — genuinely matter.
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Tuesday, August 4, 2026
Polls open 6:00 AM — close 7:00 PM. A valid Missouri photo ID is required to vote in person.
Citations
We are asking you to vote a certain way, so you are entitled to see where the numbers come from. Official ballot text, independent fiscal analysis, and non-partisan reporting — all linked in full.
Certified ballot titles, full amendment text, and official fiscal notes.
Full official title, provisions, supporters, opponents, and campaign finance.
Full official title, provisions, supporters, opponents, and campaign finance.
Distributional analysis: ~$40,000 average cut for the top 1%; $535 average increase for households earning $50,000–$80,000.
Senior household impact: ~$335 million more in total taxes, averaging ~$365 per senior household.
Estimate that roughly 80% of Missourians would see a net tax increase; list of services newly subject to sales tax.
Non-partisan voter guide, certified ballot language, and fiscal note summaries for each measure.
Reporting on the arguments for and against Amendment 5.
Analysis of how the congressional-district requirement changes which measures can pass.
Reporting that Amendment 4 bundles the district requirement with foreign-contribution and petition-fraud provisions, and that a Cole County judge struck those references from the ballot summary.
Federal ban on foreign national contributions, and the FEC's position on its scope.
Text of the federal prohibition on foreign national contributions.
Official registration status, sample ballot, and polling place lookup.
Contact information for every county and city election board.
Where sources disagree or the law is unsettled, we say so on the page rather than picking the most convenient version. The tax estimator is an illustration calibrated to published analysis, not a prediction of any individual household’s bill — its assumptions are documented inside the tool.