Early voting for the Aug. 4 primaries in Missouri is about to start. Voters can cast no-excuse absentee ballots starting July 21, and excused voting is already underway.  

On the ballot this year are four state questions that have big implications for issues including the state income tax and the initiative petition process. Those questions are:

• Amendment 1 asks voters to reapprove a 0.1% state sales tax that funds soil and water conservation projects and state parks and historic sites.
• Amendment 2 asks if the position of county assessor in all charter counties, like Jackson County, should be an elected position.
• Amendment 4 asks if the Missouri Constitution should be amended to make it harder to pass citizen-led initiative petitions.
• Amendment 5 asks if state lawmakers should be directed to eliminate the state income tax and the General Assembly given the authority to raise state sales taxes and broaden the range of goods and services that can be taxed without needing additional voter approval to speed up that process.

Those are only the statewide issues. Voters are likely to see longer ballots as local municipalities and counties place their own questions on the ballot. For example, Kansas City voters will also see four bond questions and a sales tax question on the local ballot.

As for Missouri, Amendments 4 and 5 are likely to be the most contested and closely watched issues in August, with millions of dollars already being poured into campaigns both for and against the amendments. 

Republican Gov. Mike Kehoe said in a press release the August date was necessary to give lawmakers more time to prepare for Amendment 5’s implementation if it does pass. 

But the shorter time frame also means opposition campaigns have less time to organize. August turnouts are typically lower than the general election in November and tend to skew more Republican. 

However, high-profile issues have bumped up voter participation in the past, like when the “right-to-work” issue and Medicaid expansion were on the ballot in 2018 and 2020, the Missouri Independent found.

Here’s a breakdown of each of the measures.

Soil conservation and state parks

The Missouri parks, soils and water state sales tax is a 0.1% tax that goes toward state parks and historic sites and water and soil conservation efforts, subdivisions of the Department of Natural Resources. If renewed, the state sales tax would remain at 4.225%.

The tax has been in place since the 1980s and needs reapproval every 10 years. When it was last on the ballot in 2016, it received 80% approval. On average, it costs each Missourian about $10 per year.

The tax raises about $140 million each year, which is then split evenly between the two programs. 

For state parks and historic sites, the tax supports the upkeep of trails, facilities and overnight accommodations. It also funds things like visitor centers and accessibility experiences. 

Missouri is one of only eight states that offer free entry, facilitated by the tax, to state parks and historic sites regardless of residency.  

The tax constitutes a large part of the state parks division’s budget. It brought in $69.9 million in 2025, representing 75% of the division’s total revenue. The rest comes from camping fees, donations and federal funding.

On the soil and water conservation side, the tax funds things like the Soil & Water Cost-share Program. The voluntary program allows farmers and other agricultural landowners to receive reimbursement or other financial incentives for implementing soil erosion prevention or water quality improvement measures.

DNR on its website credits the tax for reducing the amount of topsoil lost every year from 10.8 tons per acre to 4.8 tons per acre.

The tax would expire in 2028 if voters choose not to renew. The programs would instead have to rely on whatever amount of general revenue the General Assembly chooses to allocate. For fiscal year 2027, only $214,970 was appropriated for state parks.

County assessors

Amendment 2 would require the position of county assessor to be an elected official in all counties, including charter counties.

The issue is specifically tied to Jackson County, the only county in the state to have the assessor appointed by the county executive. The other charter counties in the state — Jefferson, St. Charles, St. Louis and Clay counties — already have to elect their assessors due to a 2010 constitutional amendment.

While only Jackson County would be impacted, a statewide constitutional amendment was needed because it was the only thing that could override the 2010 amendment.

Voters in Jackson County voted to have elected county assessors once already. In November, the measure was approved by 88%. 

The question follows outcry over increases in property assessments during the last two reassessment cycles, which eventually led to the ouster of then-County Executive Frank White Jr.

Initiative petitions

Amendment 4 would change the initiative petition process to require measures to pass in all eight congressional districts instead of by a simple statewide majority. 

That means as few as 5% of voters statewide could reject a measure and cause it to fail.

The new approval requirements would only apply to citizen-led petitions. Issues placed on the ballot by the General Assembly, such as the proposed state income tax elimination, would still only need a simple statewide majority to pass. 

Amendment 4 was passed during the 2025 special session after multiple attempts had failed in the regular session.

Citizen petitions have been used to force votes on issues like Medicaid expansion, a sales tax cap, marijuana legalization, paid sick leave, abortion rights and sports gambling. 

Under the proposed rules, most of those amendments would have failed, according to analysis by the Missouri Independent.

Missouri Republicans have long decried the use of initiative petitions, saying the measures are backed by out-of-state money and used to circumvent the legislature. 

Republican priorities have also been backed by out-of-state money before, including the current proposal to eliminate the state income tax, which has backing from a Delaware corporation that is not required to disclose its donors. 

Opponents of Amendment 4 have called it an attack on direct democracy and equal voting power.

State income tax elimination

Amendment 5 would direct lawmakers to eliminate the state income tax. To achieve that goal, the General Assembly would have carte blanche authority for the next five years to raise the state sales tax and expand the base of taxable goods and services without needing additional voter approval. 

The measure imposes no guidelines on how lawmakers choose to go about eliminating the income tax or on what could or couldn’t be taxed. 

The state’s top income tax rate is currently 4.7% on income of more than $9,191.

Local governments would have to make one-time adjustments to property taxes, local sales and use taxes or earnings taxes if local sales tax revenue were to increase as a result of the General Assembly’s actions. However, the adjustments cannot affect school funding. 

Eliminating the state income tax has been a top priority for Kehoe and Republican lawmakers. They say it is necessary to boost Missouri’s economic growth and increase its competitiveness.

Opponents have argued that the move will shift tax burdens from Missouri’s wealthiest to those least able to weather increased taxes. Seniors, low-income workers and local government officials have all voiced concerns about the plan.