Missouri voters heading into the August 4, 2026 election are facing a series of decisions that extend beyond routine primary races. Alongside selecting party nominees for state and federal offices, voters will also decide on multiple proposed constitutional amendments that could reshape how the state governs itself and how it raises revenue.
1The August ballot is a primary election, meaning voters will first choose party candidates for races including the Missouri House of Representatives, Missouri Senate in select districts, and the United States House of Representatives. However, the constitutional amendments are expected to draw significant attention because they would alter long-standing structures in state government.
Before any of those decisions can be made, voters must be registered by Wednesday, July 8, 2026. That deadline applies to all new registrations and updates. Missourians can confirm their registration status or make changes through the Missouri Secretary of State’s election system.
Amendment 2 focuses on county-level administration of property assessments. In practical terms, it adjusts how county assessors are selected and trained. While supporters argue the measure improves consistency and professionalism in property valuation, the change is largely procedural and is not expected to directly affect most households in their day-to-day finances.
Amendment 4 deals with the process used to approve citizen-initiated constitutional amendments. Under current law, a proposed constitutional amendment placed on the ballot by citizens passes if it receives a simple majority of statewide votes. Amendment 4 would change that threshold by requiring not only a statewide majority, but also additional approval across Missouri’s congressional districts.
Supporters of the proposal argue that this structure ensures that constitutional changes reflect a broader geographic consensus rather than being driven primarily by population centers. Critics, however, contend that the change would make it significantly more difficult for citizens to amend the constitution, even when a majority of voters statewide support a proposal. In effect, the amendment introduces a second layer of approval that could allow a measure to fail despite winning overall statewide support.
To illustrate the practical effect, under the current system a proposal supported by 55 percent of Missouri voters would pass. Under Amendment 4, the same proposal could fail if it does not also achieve majority support in each required congressional district. Opponents argue this shifts power away from a simple statewide majority and increases the likelihood that smaller geographic regions could block changes supported by most voters across the state.
Amendment 5 represents the most significant potential change on the ballot in terms of fiscal policy. It proposes beginning a process to eliminate Missouri’s individual income tax while restructuring how the state collects revenue. Although the amendment does not establish a specific new sales tax rate, it authorizes lawmakers to adjust tax structures in order to replace revenue lost from the income tax.
Supporters of the measure argue that reducing or eliminating income tax would allow residents to keep more of what they earn and could make Missouri more competitive economically. Opponents caution that shifting away from income-based revenue would likely increase reliance on sales taxes and other consumption-based fees, which tend to fall more heavily on lower-income households that spend a larger proportion of their income on basic necessities.
1In effect, critics argue the amendment could shift Missouri’s tax burden away from income and toward spending, a change that would have different impacts depending on household income levels. Higher-income households that save and invest more of their earnings may see proportionally larger benefits, while working-class families could be more exposed to increases in the cost of everyday goods and services if consumption taxes rise over time.
Together, the amendments present voters with choices that go beyond standard policy debates. Amendment 2 adjusts administrative procedure, Amendment 4 changes how citizen-driven constitutional amendments are approved, and Amendment 5 addresses the structure of state taxation itself.