Colorado voters passed two big money measures on November 3, 2026. Amendment 87 replaces our flat 4.4% state income tax with graduated brackets starting in tax year 2027, and Proposition NN lets the state keep money that would have gone back to us as TABOR refunds and spend it on K-12 schools and children's programs. Neither one raises property tax rates.
I've had a lot of clients in Fort Collins, Loveland, and Greeley ask me what these mean for them, so here's the plain-English version.
A quick note on the name: if you searched for "Prop NNN," you're in the right place. There's no Proposition NNN on the Colorado ballot. The measure people mean is Proposition NN (two N's).
Watch on YouTube: Why High Earners are Leaving Colorado for Wyoming (Amendment 87)
What passed on November 3, 2026?
Both measures passed, based on news tallies shortly after Election Day. Amendment 87 passed with about 51.4% of the vote, and Proposition NN passed with about 57% (Denver Gazette). These numbers are unofficial until the state certifies the results.
A competing measure, Proposition 136, would have capped the income tax rate at 4.4%. It was trailing at about 47% yes in the same tally.
What does Amendment 87 change?
Amendment 87 changes Colorado's state income tax from one flat rate to six brackets, starting with tax year 2027. Under the old law, everyone paid 4.4%. Here are the new rates on taxable income, from the 2026 Blue Book:
| Taxable income | Rate |
|---|---|
| $25,000 or less | 3.7% |
| $25,001 to $100,000 | 4.2% |
| $100,001 to $500,000 | 4.4% |
| $500,001 to $750,000 | 7.4% |
| $750,001 to $1,000,000 | 7.9% |
| More than $1,000,000 | 8.4% |
According to the Blue Book, people with taxable income under about $500,000 generally pay a little less, and people above that pay more. The brackets are not adjusted for inflation. The new money goes into a "Colorado Future's Account" for K-12 education, health care, and early childhood care.
What does Proposition NN change?
Proposition NN raises the limit on how much revenue the state can keep under TABOR (the Taxpayer's Bill of Rights). Money above the old limit that would normally be refunded to taxpayers can now be kept and spent instead. It doesn't create a new tax rate.
The Blue Book estimated that Prop NN would reduce TABOR refunds by about $330 million in the 2026-27 budget year and about $521 million in 2027-28, which would eliminate refunds in those years under the forecast at the time. For the first ten years, the money has to go to K-12 schools (teacher pay, smaller classes, career and technical programs) and programs for children, with preschool and child care as a priority.
How do Amendment 87 and Prop NN relate?
They were on the same ballot and both aim at school and children's funding, but they work in different ways:
- Amendment 87 changes income tax rates. The new income tax money is exempt from the TABOR limit, and the Blue Book says it does not affect current TABOR refunds on its own.
- Proposition NN changes what happens to the surplus. It's the measure that shrinks or eliminates near-term TABOR refunds.
So if your TABOR refund disappears in 2027, that's Prop NN. If your income tax rate changes, that's Amendment 87.
Do these measures raise property taxes?
No. Amendment 87 is an income tax measure and doesn't change property tax rates or assessments. Prop NN doesn't raise mill levies either. It actually keeps the state reimbursing local governments for existing property tax exemptions for seniors, disabled veterans, and Gold Star spouses.
Your property tax bill is still set locally, by your county assessor and local mill levies. Many local tax increases on the Front Range actually failed the same night.
What about selling your home?
If you're selling your primary home, Amendment 87 keeps the state tax on that income at 4.4%, not the new higher brackets. That's written right into the ballot language. It applies to the gain above the federal home-sale exclusion.
Investment property is different, since the graduated rates apply to taxable income in general. If you own rentals or land, a 1031 exchange may be worth a look. For your own situation, please talk with a CPA. I'm a Realtor, not a tax advisor.
What this means if you're moving between Colorado and Wyoming
Wyoming still has no state income tax. Colorado will now have graduated brackets starting in 2027. For most households earning under $500,000, the Colorado income tax change is small. For higher earners, the gap between the two states gets wider.
I'm licensed in both Colorado and Wyoming, so I help a lot of buyers compare homes in Fort Collins, Loveland, and Greeley with homes just across the line in Cheyenne. Taxes are one piece of that decision, along with commute, home prices, and lifestyle.
Frequently asked questions
What's the difference between Amendment 87 and Proposition NN?
Amendment 87 changes Colorado's income tax from a flat 4.4% to graduated brackets from 3.7% to 8.4%, starting in 2027. Proposition NN lets the state keep TABOR surplus money for schools and children's programs instead of refunding it.
Does either measure raise my property taxes?
No. Amendment 87 is an income tax measure, and Proposition NN doesn't change mill levies. Property taxes are still set by your county and local districts.
When do the new income tax brackets start?
Tax year 2027.
Will I get a TABOR refund in 2027?
Under the Blue Book's estimates, Proposition NN would eliminate TABOR refunds in the next couple of budget years. That depends on actual state revenue, so watch for updates during tax season. This is separate from a normal refund for overpaying your income tax.
Is my home sale taxed at 8.4% now?
No. The ballot language keeps income from selling a principal residence at 4.4%. Talk to a CPA about your specific sale.
Is "Prop NNN" a real measure?
No. People sometimes search for "Proposition NNN," but the 2026 Colorado measure is Proposition NN.
Thinking about buying or selling in Northern Colorado or Cheyenne? Reach out and I'll walk you through the numbers for your area.
This article is for general information only and isn't tax or legal advice. Election results are unofficial until certified by the Colorado Secretary of State.
Mariah Jeffery, Realtor, licensed in Colorado and Wyoming Coldwell Banker The Property Exchange
Sources: 2026 Colorado Blue Book; Colorado Legislative Council, Amendment 87; Denver Gazette election results; Colorado Sun TABOR explainer; KUNC on Proposition NN