Graduated Income Tax
Replaces Colorado's flat 4.4% income tax with brackets - a small cut below $500K, a steep increase above it.
Cheat sheet The whole measure in 30 seconds tap to open
Creates a graduated state income tax, spends the additional revenue on K-12 education, health care and early childhood care, and exempts that revenue from the state's constitutional revenue limit.
Keeps the constitutional requirement for a single flat income tax rate.
Strongest case for
It cuts taxes for 97 percent of taxpayers, including most households and small businesses, and raises them only on top earners who can afford it - a dollar taxed on someone earning $30,000 is a far bigger hardship than a dollar taxed on someone earning $1 million.
Strongest case against
It is a multibillion-dollar tax increase that makes Colorado less competitive for starting and growing a business and may push high earners and employers out of the state, costing jobs at every income level.
Watch out: Two things voters most often get wrong. First, it does not touch TABOR refunds - the new money is exempt from the limit, so refunds stay as they are. Second, the brackets are not indexed to inflation, so bracket creep pulls more income into higher rates over time. And if Proposition 136 passes too, the Blue Book says the outcome is unclear.
What this actually does
Colorado taxes everyone's income at the same flat 4.4 percent, and the constitution requires that flat rate. This measure removes that requirement and creates six brackets starting in 2027. Rates go down for taxable income under $500,000 and up sharply above it - as high as 8.4 percent on income over $1 million. Anyone with taxable income below about $511,000 pays less, but at most $325 less. The roughly $2 billion a year it raises must be spent on K-12 education, health care, and early childhood care, on top of what the state already spends on those things.
What your vote means
Creates a graduated state income tax, spends the additional revenue on K-12 education, health care and early childhood care, and exempts that revenue from the state's constitutional revenue limit.
Keeps the constitutional requirement for a single flat income tax rate.
On every measure, yes means change something and no means leave it alone.
Easiest thing to get wrong
Read this twice
Two things voters most often get wrong. First, it does not touch TABOR refunds - the new money is exempt from the limit, so refunds stay as they are. Second, the brackets are not indexed to inflation, so bracket creep pulls more income into higher rates over time. And if Proposition 136 passes too, the Blue Book says the outcome is unclear.
The case each side makes
Straight from the state's official booklet, shortened. These are arguments as each side makes them — not findings of fact, and not our view.
Why people say yes
- It cuts taxes for 97 percent of taxpayers, including most households and small businesses, and raises them only on top earners who can afford it - a dollar taxed on someone earning $30,000 is a far bigger hardship than a dollar taxed on someone earning $1 million.
- It funds schools, health care and child care when they are most at risk: Colorado schools are significantly underfunded and federal policy changes make Medicaid cuts more likely.
- A graduated income tax is not an experiment - the federal government and 27 other states already use one, and it offsets sales and property taxes that fall hardest on lower-income households.
Why people say no
- It is a multibillion-dollar tax increase that makes Colorado less competitive for starting and growing a business and may push high earners and employers out of the state, costing jobs at every income level.
- Because the brackets are not adjusted for inflation, more and more taxpayers will be pulled into the higher rates every year.
- It attacks the fair, predictable flat tax TABOR guarantees and permanently expands government - the state should better prioritize the tens of billions it already collects instead of switching to a complicated new system.
Where this sits politically
high confidence Filed by the president of the Bell Policy Center, a progressive fiscal think tank and a former Democratic legislator. Funded by the state's progressive policy and labor organizations. A graduated income tax raising revenue for schools and health care is a defining progressive fiscal position.
How we place the needle and why it is an estimate, not a measurement
We read four things, all of them public and documented:
- Who filed it and what they are affiliated with.
- The recorded party vote, where one exists. On this ballot only Proposition NN has one, because it is the only measure the legislature referred.
- Which side of the political infrastructure is paying for each campaign.
- Which direction the policy moves compared with current law.
Confidence is high when all four point the same way and low when they contradict each other. A low-confidence needle is telling you the measure genuinely does not sort neatly — Amendment 86 is the clearest case, with conservative sponsors and anti-gerrymandering content.
This is our editorial read, not a measurement. A citizen initiative has no party sponsor, so for 13 of these 14 measures there is no official partisan label to report — only inference. Use the needle to get oriented, then read the measure and decide for yourself.
What it costs
Raises an estimated $2 billion more in income tax in the first full year, exempt from the TABOR limit. The roughly 46,300 taxpayers with federal AGI above $1 million pay about $26,085 more on average; every income group below $500,000 sees an average cut between $1 and $325. Current TABOR refunds do not change.
Who it touches: Every Colorado income taxpayer, individual and business. Taxable income under about $511,000 goes down; above that it goes up.
Who put it on your ballot
Progressive / Democratic-aligned
People who filed it
Campaigning for it
Campaigning against it
Chris deGruy Kennedy is the campaign co-chair and leads the Bell Policy Center, a progressive fiscal think tank; he is a former Democratic state representative. The funding coalition is the state's progressive policy and labor infrastructure.
A lawsuit filed in September 2026 sought to remove Amendment 87 from the ballot.
Who is paying for the ads
Money for it
Money against it
What the money tells you
Supporters have raised far more in dedicated money, but the opposition runs mostly through anti-tax slate committees and through Proposition 136, the counter-measure on the same ballot. A lawsuit also sought to strike Amendment 87 from the ballot in September 2026.
Figures are a late-September 2026 snapshot from TRACER campaign-finance filings and will have moved since. A committee marked slate spreads one total across several measures — do not read its number as spending on this measure alone.
Questions people ask
Common questions (6)
The things people want to know before they vote, answered from primary sources where they exist. Every answer was drafted with AI assistance from retrieved documents, then read and approved by a person. Figures carry the year they refer to.
How do Colorado's income tax rates compare with other states today, and how would they change under this measure?
Colorado currently taxes all income at a flat 4.4 percent, but Measure A87 would replace this with a graduated system peaking at 8.4 percent.
According to 2026 Tax Foundation data, state income tax structures compare as follows: * Flat tax: 15 states, including Colorado. * Graduated tax: 27 states, where rates increase as income rises. * No individual income tax: 8 states.
Under Measure A87, Colorado would switch to a graduated system with six brackets. Taxable income under $500,000 would be taxed at lower rates, saving those taxpayers up to $325. Income above $500,000 would face sharply higher rates. The top marginal rate would reach 8.4 percent on income over $1 million.
If passed, Colorado's new 8.4 percent top rate would be higher than most states. However, it would remain below the highest top rates in California (13.3 percent), Hawaii (11 percent), and New York (10.9 percent).
Supporters emphasize the measure provides a tax cut for everyone earning under $500,000 while raising an estimated $2 billion annually for education and health care. Opponents point out that the measure nearly doubles the tax rate on high earners and exempts the new money from the state's constitutional revenue limit, known as TABOR.
How many Colorado taxpayers would pay more, and how many would pay less?
Under Amendment 87, approximately 97 percent of Colorado taxpayers would pay less in state income tax, while about 64,000 taxpayers would pay more.
According to the 2026 state fiscal note, the measure replaces Colorado's flat 4.4 percent income tax with a graduated system. A 2026 AARP report notes Colorado is currently one of 14 states with a flat rate. The proposed brackets lower taxes for those with taxable income below roughly $511,000. The fiscal note estimates these taxpayers will save between $1 and $325 annually.
According to a 2026 legislative analysis, taxes would increase for the roughly 64,000 taxpayers above that threshold. The fiscal note estimates that about 46,300 taxpayers with incomes over $1 million would pay an average of $26,085 more per year.
Supporters emphasize that 97 percent of Coloradans receive a tax cut while generating an estimated $2 billion to $2.7 billion in new annual revenue for public schools, health care, and early childhood programs. Opponents argue that relying on a small number of high earners could drive wealthy taxpayers out of the state and shrink the tax base.
This new revenue would be exempt from the Taxpayer's Bill of Rights, or TABOR, a constitutional limit on how much money the state can keep and spend.
How many other U.S. states currently use a graduated income tax system compared to a flat tax rate, and what are their top bracket rates?
As of 2026, 27 states and the District of Columbia use a graduated income tax system, while 14 states use a flat tax rate. A graduated tax means rates increase as a taxpayer's income rises. A flat tax applies the same rate to all taxable income.
According to 2026 data from the Tax Foundation, top bracket rates in graduated-tax states vary widely: * North Dakota has the lowest top rate at 2.5 percent. * California has the highest top rate at 13.3 percent. * Hawaii has the second-highest at 11 percent.
Colorado currently uses a flat 4.4 percent rate. If Measure A87 passes, Colorado would join the states with a graduated system. It would apply a top rate of 8.4 percent to taxable income over $1 million.
Supporters of graduated taxes emphasize that they reduce costs for lower-income earners. The state fiscal note estimates Measure A87 will provide a tax cut for Coloradans earning under $500,000. Conversely, opponents argue that flat rates or having no income tax keeps a state competitive. Eight U.S. states currently levy no individual income tax at all, and one state taxes only capital gains.
What percentage of Colorado taxpayers currently report taxable income above $500,000 and will be subject to the new higher tax brackets under this measure?
There is no exact, up-to-date official percentage of Colorado taxpayers who report taxable income above $500,000, but available estimates place it between 1.4 percent and 3 percent.
- The Protect Colorado's Future campaign estimates that 97 percent of taxpayers will see a tax cut. This implies 3 percent or fewer earn enough to face the higher brackets.
- A 2019 Colorado Office of the State Auditor report analyzed full-year resident returns. Out of 2.25 million returns reporting at least $10,000 in Adjusted Gross Income (AGI)—a measure of total income minus specific deductions—about 32,272 returns reported $500,000 or more. This is roughly 1.4 percent.
- The 2026 legislative fiscal note estimates that 46,300 taxpayers report an AGI above $1 million. It does not provide a specific count for the $500,000 to $1 million range.
Supporters use these figures to argue the measure provides a tax cut for the vast majority of working Coloradans. They say it only raises rates on a wealthy fraction to fund education and health care. Opponents argue that heavily taxing this small percentage of high earners could drive them out of the state. They warn this would reduce the overall tax revenue Colorado relies on.
How does the projected $2 billion in new revenue compare to what Colorado currently spends annually on K-12 education, health care, and early childhood care?
The projected $2 billion in new revenue from Measure A87 equals roughly 7 percent of the $27.8 billion Colorado currently spends across K-12 education, health care, and early childhood care.
According to state budget documents and legislative reports, current annual spending breaks down as follows: * Health care: $19.2 billion proposed for the Department of Health Care Policy and Financing for fiscal year 2026-27. * K-12 education: Over $7.8 billion appropriated to the Department of Education for fiscal year 2026-27. * Early childhood: $803 million appropriated to the Department of Early Childhood for fiscal year 2025-26.
Supporters argue this $2 billion is a substantial investment, noting it is more than double the state's entire early childhood budget and provides a dedicated funding stream exempt from the state's constitutional revenue limit, known as TABOR. Opponents argue that $2 billion is a small fraction of the state's existing obligations, pointing out that the health care budget alone is nearly ten times that amount and has been rapidly growing.
How will the proposed graduated income tax brackets apply to small businesses and corporations that currently pay the flat 4.4 percent state income tax?
Under Measure A87, both corporations and small businesses will transition from the current flat 4.4 percent tax rate to a graduated system. Rates will range from 3.7 percent to 8.4 percent based on taxable income.
For traditional corporations, known as C-corporations, the new graduated rates will apply directly to their annual corporate net income. For small businesses structured as pass-through entities, such as LLCs and S-corporations, the business profits pass through to the owners' individual tax returns. Those owners will pay the graduated rates on their total personal taxable income. This total includes their share of the business profits.
According to the 2026 Colorado Secretary of State ballot language, the proposed brackets starting in 2027 are: * Up to $25,000: 3.7 percent * $25,001 to $100,000: 4.2 percent * $100,001 to $500,000: 4.4 percent * $500,001 to $750,000: 7.4 percent * $750,001 to $1,000,000: 7.9 percent * Over $1,000,000: 8.4 percent
Supporters, including the Bell Policy Center, estimate the measure will reduce taxes for 95 percent of businesses. They say it will raise $2 billion annually for public services. Opponents, such as the Common Sense Institute, argue that nearly doubling the top tax rate will weaken Colorado's business climate. They warn it could drive corporations to other states. As of 2026, Colorado is one of 15 states with a flat income tax rate.
Go deeper, if you want
We had two AIs summarize this independently Material difference
Both models got the same official text, the same instructions, and could not see each other's answer. Here is each one in its own words.
Claude
Colorado taxes everyone's income at the same flat 4.4 percent, and the constitution requires that flat rate. This measure removes that requirement and creates six brackets starting in 2027. Rates go down for taxable income under $500,000 and up sharply above it - as high as 8.4 percent on income over $1 million. Anyone with taxable income below about $511,000 pays less, but at most $325 less. The roughly $2 billion a year it raises must be spent on K-12 education, health care, and early childhood care, on top of what the state already spends on those things.
Flagged: Two things voters most often get wrong. First, it does not touch TABOR refunds - the new money is exempt from the limit, so refunds stay as they are. Second, the brackets are not indexed to inflation, so bracket creep pulls more income into higher rates over time. And if Proposition 136 passes too, the Blue Book says the outcome is unclear.
Gemini
Amendment 87 changes Colorado's income tax from a single flat rate to a graduated system. It lowers taxes on the first $500,000 a person or business earns, but raises taxes on any money earned above that amount. The extra money collected will bypass state revenue limits to pay for public schools, health care, and early childhood programs.
Flagged: The new tax brackets are not adjusted for inflation, meaning more of a taxpayer's income will naturally fall into higher tax brackets over time.
Where they came apart
- This is the one place where the two summaries would leave a voter with meaningfully different impressions.
- Gemini writes that the measure 'lowers taxes on the first $500,000 a person or business earns.' That overstates the cut. Under the Blue Book's own table, the $100,001-$500,000 bracket stays at exactly 4.4% — unchanged — and the total reduction tops out at $325 no matter how much you earn below the threshold. Claude states the $325 cap explicitly.
- Gemini omits the single most common misconception, which the Blue Book devotes a whole question to: the measure has no effect on TABOR refunds, because the new revenue is exempt from the limit. Claude leads its catch with it.
- Gemini does not mention the collision with Proposition 136 on the same ballot. Claude flags that the Blue Book calls the outcome 'unclear' if both pass.
- Both models independently caught that the brackets are not indexed to inflation, so bracket creep pulls more income into the higher rates over time.
The comparison notes were written by Claude — one of the two models grading the contest — which is exactly why both summaries are printed above them in full.
The other model's take on cost and reach second opinion
Cost: Increases state income tax revenue by an estimated $2 billion in its first full year. This money is exempt from TABOR limits and will be directed to education and health care programs.
Who it touches: All Colorado taxpayers (individuals and businesses), as well as public schools, health care programs, and early childhood education providers.
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Source: 2026 Colorado State Ballot Information Booklet (the "Blue Book"), Legislative Council of the Colorado General Assembly, Research Publication No. 842. Read the original.