Fact-check analysisVerified as of August 5, 2026Curated by FactVerifyElectionsTaxesMissouri

Mostly True

Missouri voters have overwhelmingly rejected Amendment 5, the GOP-backed plan to phase out the state income tax and replace it with higher sales taxes

Verdict: Mostly True. Missouri voters rejected Amendment 5 on August 4, 2026, and the measure would have phased out the individual income tax while authorizing broader sales and use taxes; however, the supplied evidence does not establish an overwhelming margin or formal Republican Party backing.

What was submitted

The Claim

Missouri voters have overwhelmingly rejected Amendment 5, the GOP-backed plan to phase out the state income tax and replace it with higher sales taxes

At a glance

Key Evidence

Verified August 5, 2026

KOMU reported on August 5, 2026, that Missouri voters rejected Amendment 5 in the August 4 election.
The measure proposed gradually phasing out Missouri’s individual or state income tax.
The proposal paired that phaseout with authority to raise or expand sales and use taxes, including taxation of additional services, to offset the difference.

The reporting

What the Evidence Shows

What is established

Republican Gov. Mike Kehoe was a leading supporter, and Republican legislators and Grover Norquist were reported speaking in favor of Amendment 5.

Context and caveats

The supplied election report confirms rejection but provides no vote totals or percentages, so “overwhelmingly” cannot be verified from the approved excerpts.

The evidence supports describing the proposal as backed by Republican officials and aligned supporters, but it does not show that the Republican Party formally endorsed it as an organization.

The approved materials indicate that the specific future sales-tax rates, goods, services, and exemptions were not predetermined.

The available evidence does not establish the size of Amendment 5’s defeat.

It is uncertain whether “GOP-backed” is intended to mean support from Republican officials and aligned groups or a formal Republican Party endorsement.

Primary trail