Summary
- What is it? A constitutional change that phases out the state income tax and lets lawmakers raise and expand the sales tax to replace it.
- Is it a tax cut? It’s a tax swap. Income tax out; sales tax up. Whether you pay more depends on how much you earn vs. spend.
- How big a deal? The income tax is about two-thirds of state general revenue. Replacing it could push the 3% sales tax to as much as 11.5%, or tax new things like services.
- Do I lose my vote? For five years, on these tax increases — yes. It sets aside the Hancock voter-approval rule and overrides the 2016 ban on taxing services.
- Is it “revenue-neutral”? That’s a forecast. Estimates for last year’s smaller capital gains cut ranged from ~$111 million to ~$625 million — so a “revenue-neutral” promise on a far bigger change deserves scrutiny.
- Would schools lose money? Not automatically — the risk is stability. This year a ~$138 million shortfall cut ~$245 per student mid-year. Amendment 5 scales up that kind of risk.
- Like Kansas? Same growth promise, which failed there (repealed in 2017). But Missouri’s would be locked in the constitution — no easy undo.
- See your district: use our lookup tools to find your local/state/federal mix and judge the risk yourself.
Bottom line: weigh the appeal of ending the income tax against leaning on one revenue source, losing your direct tax vote for five years, and locking it all into the constitution.
The Full Story: What is Amendment 5?
It’s a proposed change to the Missouri Constitution on the August 4, 2026 ballot. It would phase out the state individual income tax over time and authorize lawmakers to raise or expand the sales tax to offset the lost revenue. It doesn’t set the new tax rates itself — the official ballot summary says the financial impact is “unknown” until lawmakers pass the laws to carry it out.1
When do I vote on it?
August 4, 2026 — the primary election. The governor moved it from the November ballot to August.2
Does it cut my taxes?
It would phase out the income tax, but it would also let the state raise the sales tax to make up for it. So it’s better understood as a tax swap than a simple cut. Whether you’d pay more or less depends on how much you earn versus how much you spend. As a reference point, a household at Missouri’s median income of about $70,000 pays roughly $3,000 in state income tax today.3
How big is the income tax in Missouri’s budget?
It’s the largest single source — about two-thirds (roughly 65%) of the state’s general revenue, the main pot that funds schools and other services. Sales tax provides about 22%.4
How would the state replace that money?
By raising the sales tax, expanding it to new goods and services, or both. If nothing new were taxed, the general-revenue portion of the state sales tax would have to rise from 3% to as much as 11.5% — about an 8.5-percentage-point increase on that portion (not on the full combined rate you pay at the register).5
Would it raise taxes on things that aren’t taxed now?
It could. Amendment 5 would authorize lawmakers to tax “transactions involving any goods and services” — including services like haircuts, home repair, and car repair that aren’t taxed today. In 2016, voters banned new sales taxes on services; Amendment 5 would override that protection. Whether and how much lawmakers actually would tax is left for them to decide later.6
Is it true I’d lose my vote on tax increases?
For five years, on these decisions, yes. The Hancock Amendment normally requires voter approval for big state tax increases — it’s why sales-tax questions go on the ballot. Amendment 5 would set that aside for five years so lawmakers could raise and expand the sales tax without asking voters. You’d still elect your legislators, but you’d lose the direct vote on the tax increases themselves.7
Supporters say it’s “revenue-neutral.” Is it?
That’s a forecast, not a guarantee. And Missouri’s recent track record makes the forecast hard to trust: estimates for last year’s capital gains tax cut ranged from the low hundreds of millions to roughly $625 million, and the state’s budget director later projected about $500 million for this year — well above the original figure. If forecasts on a smaller change varied that much, a “revenue-neutral” promise on a much bigger change deserves real scrutiny.8
Would schools lose money?
Not automatically, and not on day one — the risk is about stability, not an immediate cut. Amendment 5 would weaken the state’s largest revenue source and lean the rest on future legislative choices and forecasts. The ballot summary (rewritten by a court in June 2026) says the measure would require local tax cuts “without reducing school funding” if local sales tax rises — but that promise covers only local taxes. It does not protect the state’s share — the foundation formula, transportation, and special education — funded largely by the income tax being phased out. So the honest answer is that Amendment 5 puts school funding at risk, mainly on the state side, if the revenue swap falls short.
Has anything like this happened recently?
Yes, on a smaller scale. This year, the part of school funding that relies on lottery, gaming, and cigarette taxes came up about $138 million short of projections, and the state reduced funding by roughly $245 per student mid-year, even dipping into Capitol-renovation funds. That’s not proof of what Amendment 5 would do — it’s a separate, earmarked pot — but it’s a live example of how volatile, consumption-based revenue can miss its forecast and reach schools fast.9
Why do supporters want this?
They argue that ending the income tax will make Missouri more competitive — attracting people, jobs, and businesses — and let Missourians keep more of what they earn. They also note the cuts are gradual, tied to revenue growth, not all at once.10
Isn’t a gradual, phased plan safer than doing it all at once?
The phase-in is more cautious than, say, Kansas’s overnight cuts, and that’s a fair point. But the gradual design doesn’t address the two biggest risks: losing the diversification of a mixed tax system, and locking the change into the constitution so it can’t easily be undone.
How is this like what Kansas did?
Kansas cut income taxes deeply in 2012–13 on the promise of growth. Growth didn’t follow; revenue collapsed, schools were cut, and lawmakers repealed the cuts in 2017. Some of the same advisers are behind Missouri’s effort, and the core growth promise is the same.11
How is it different from Kansas— and why might that be worse?
Kansas could undo its mistake with a simple law, and did. Amendment 5 would write income-tax elimination into the constitution, so reversing it would require another statewide vote. Missouri also leans harder on its income tax than Kansas did and lacks the tourism- or resource-driven tax base some no-income-tax states rely on. And Kansas only cut rates; Missouri proposes full elimination.12
Does this hit some districts harder than others?
Yes. Rural districts tend to be more exposed, because they often rely more heavily on state aid (they have less local property wealth to tax) and have less room to backfill a shortfall locally. In many small towns the school is also one of the largest employers, so a funding hit ripples through the local economy. Use the lookup tool to see your district’s state share.
Is the sales tax really more volatile than the income tax?
It depends on the type of downturn, so we don’t rest the argument there. The stronger point is diversification: a mix of income and sales taxes is steadier than either alone, because they tend to drop at different times. Amendment 5 would remove that hedge.
Didn’t Missouri already change its taxes recently?
Yes. Last year Missouri became the first state to fully stop taxing capital gains (profits from selling stocks and assets). That already removed one source of revenue — and it’s the change whose cost estimates ranged widely and kept climbing, as noted above.13
Who’s for it and who’s against it?
Supporters include the governor, who made it a top priority, and a campaign committee backing it. Opponents include a range of groups — from a Realtors-funded committee to senior, education, and budget-policy organizations — and notably some Republican legislators joined Democrats in voting against putting it on the ballot.14
Is Amendment 5 settled, or could it still change?
It is set for the August 4 ballot. On June 5, 2026, a state appeals court kept it on the ballot but ruled the original summary didn’t fairly inform voters, and it rewrote the language voters will see (that ruling could still be appealed to the Missouri Supreme Court). Even with the clearer summary, the details of how the measure would be carried out — which things get taxed and at what rates — aren’t spelled out; lawmakers would decide that later.15
How should I decide?
Weigh the tradeoff honestly. Amendment 5 offers the appeal of ending the income tax. In exchange, it would lean the state more heavily on one revenue source, remove your direct vote on tax increases for five years, and lock the change into the constitution — with key details left to future legislatures. Weigh the promise against those uncertainties, and decide for yourself.
SOURCES
1. Amendment 5 would phase out the individual income tax and authorize lawmakers to expand sales/use taxes to replace it; the ballot summary describes the financial impact as unknown until implementing legislation passes. On the August 4, 2026 ballot. Missouri Independent, June 1, 2026.
2. Gov. Mike Kehoe moved the measure from the November to the August 4 primary ballot. Missouri Independent, April 21, 2026; St. Louis Public Radio, May 22, 2026.
3. Missouri median income about $70,000 pays roughly $3,000 in state income tax (Missouri Dept. of Revenue calculator); top rate 4.7%. KCTV5, May 23, 2026.
4. Income tax about 65% of state general revenue; sales tax about 22%. Missouri Independent, April 21, 2026.
5. Without broadening the base, the 3% general-revenue portion of the state sales tax would have to rise to as much as 11.5% — about an 8.5-point increase on that portion. Missouri Independent, June 1, 2026; Missouri Budget Project.
6. Amendment would authorize taxing “transactions involving any goods and services”; the 2016 voter-approved ban on taxing services would not apply to a plan passed under it. Missouri Independent, April 21, 2026.
7. The Hancock Amendment generally requires a public vote on large tax increases; Amendment 5 provides a five-year window to bypass it. KCTV5, May 23, 2026.
8. Capital gains cut estimates ranged from the low hundreds of millions to about $625.6 million; the state budget director later projected about $500 million for the current fiscal year. RSM US analysis of the fiscal note (2025); Missouri Independent, December 18, 2025.
9. FY2026 shortfall about $138 million; about $245 per-pupil mid-year reduction; Capitol-renovation funds tapped. Missouri Independent, April 23, 2026.
10. Supporters’ competitiveness/growth rationale and gradual, trigger-based design. Missouri Independent, April 21, 2026; KCTV5, May 22, 2026.
11. Kansas 2012–13 cuts, revenue shortfalls, school cuts, and 2017 repeal; shared advisers. Center on Budget and Policy Priorities (2018); reporting on Missouri advisers (2024).
12. Reinstating the income tax would require a new constitutional amendment; Missouri’s heavier income-tax reliance and lack of a resource- or tourism-driven tax base; Kansas cut rates rather than eliminating the tax. KCTV5, May 23, 2026; Missouri Independent, April 21, 2026.
13. Missouri first state to fully exempt capital gains; cost estimates ranged widely and were revised upward. Missouri Independent, December 18, 2025; RSM US (2025).
14. Supporters include the governor and the Missouri Promise PAC; opponents include Missourians for Fair Taxation (Realtors-funded), the Missouri Budget Project, AARP, and others; nine House Republicans and three Senate Republicans opposed putting it on the ballot. Missouri Independent, April 21 and June 2, 2026.
15. On June 5, 2026, the Missouri Western District Court of Appeals kept Amendment 5 on the August 4 ballot but found the original ballot summary insufficient and rewrote it; the ruling could be appealed to the Missouri Supreme Court. The rewritten summary tells voters the measure would “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.” Implementation details left to the legislature. Missouri Independent and KOMU, June 5, 2026.
Paid for by Across the Aisle for Missouri Public Schools, AAMPS PAC, Jacque A. Cowherd, Treasurer