Colorado ballot · Election Day, Tuesday, November 3, 2026

Propositions 134 and 135 · filed as Initiatives #109 and #110

Vote no on 134 and 135.

Two measures are on Colorado’s November ballot. One restricts who can play on K‑12 and college sports teams that are designated by sex, and it defines sex by reproductive biology. The other bans any surgery on anyone under 18 to alter their biological sex characteristics, and bars public money from paying for it. If passed, both take effect January 1, 2027.

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34 days until the election

Two sets of numbers

On your ballot they are Propositions 134 and 135.

The Secretary of State has published the 2026 ballot listing. Initiative #109 is now Proposition 134. Initiative #110 is now Proposition 135. Same two measures, new ballot numbers.

Before the ballot numbers were assigned, the state itself called them Initiative #109 and Initiative #110. Those are filing numbers, not ballot numbers. On the ballot itself, look for 134 and 135.

One more trap. Colorado voted on a different Proposition 109 and Proposition 110 in 2018. Both were transportation-funding measures, and both failed. Searching those numbers will find you the wrong thing.

What the measures say

Quoted from the filed text, not from either campaign.

Proposition 134 · Initiative #109

School sports

Official title, in part“restricting participation in all K‑12 and collegiate school sports based on the participant’s sex as determined by certain aspects of their biological reproductive system.”

It defines sex by the reproductive cells a body is organized to produce. In its words, “female” means a person whose biological reproductive system is organized around the production of ova. “Male” is the same definition, built around sperm.
The bar runs one way. A girls’ team “shall not be open to a male student or participant.” No exception, ever. A boys’ team is closed to a girl only when a girls’ team in that sport is offered or available to her. So a girl with no girls’ team available to her may still play on the boys’ team. A trans girl has no such door. The measure counts her as male, and the bar on the girls’ team has no exception to let her through.
It covers public, charter, private and denominational K‑12 schools, and Colorado’s colleges and universities. But its only enforcement provision lets the commissioner of education act against K‑12 school districts. So it binds schools it cannot reach.
It forbids any government entity, licensing body or athletic association from even hearing a complaint against a school that complies.
Its definitions apply only inside the new article (“as used in this article 60”), not to Colorado law generally.

Proposition 135 · Initiative #110

Surgery for people under 18

Official title, in part“prohibiting surgery on a minor for the purpose of altering the minor’s biological sex characteristics.”

It defines the ban by purpose, not procedure. “Altering biological sex characteristics” means “treatment in response to a minor’s perception of sex or gender.” The same subsection then excludes three things: treatment for people “born with a medically verifiable disorder of sex development,” treatment for “acquired physical or chemical abnormalities,” and male circumcision. Those exclusions show what the measure does. The same operation stays legal when the reason for it is different.
Its funding ban names three things: “no state or federal funds, Medicaid reimbursements, or insurance coverage.” The first two are plainly public money. The third, “insurance coverage,” is not qualified, so on its face it reaches private plans too. But the measure’s own heading says only “prohibition on state funding.” How far that third term reaches is a question the text does not settle. A court would have to.
It applies to everyone under 18. The phrase “parental consent” appears nowhere in it.
It binds far more than surgeons. The ban applies to “a health‑care professional or other person.” The measure defines health‑care professional to include psychiatry, psychology, mental health therapy, pharmacy and “other healing arts.”

Read the full case against both measures

Argument by argument, quoted from the filed text, including where courts have ruled the other way.

One of those rulings is recent. On June 30, 2026, in West Virginia v. B.P.J., the U.S. Supreme Court held that Title IX and the Equal Protection Clause permit schools to limit girls’ teams to biological females. That runs against part of our case, and we say so where it applies.

Both take effect January 1, 2027 if passed. Colorado’s nonpartisan Legislative Council Staff scored both at zero fiscal impact: no state revenue, no state spending, no change to TABOR refunds.

How they pass

A simple majority. That is all either one needs.

The threshold

Both measures are statutory, not constitutional. So neither faces the 55‑percent bar Colorado sets for constitutional amendments. Each passes on a simple majority of the votes cast on it. That makes them easier to pass, not harder. It is a reason to vote, not a reason to relax.

The state’s own ballot listing says so. Each one “passes with a majority vote.” On the same page, each of the seven constitutional amendments carries the note “Requires 55% approval because it adds language to the state constitution.” These two do not.

The signatures

They got on the ballot by sample, not by count. The Secretary of State’s qualification announcements record 168,579 signatures submitted for what is now Proposition 134 and 164,922 for what is now Proposition 135. The requirement was 124,238. The state did not count them line by line. It checked a five‑percent random sample and projected. No valid‑signature count exists for either measure.

How many students

Colorado does not track how many transgender students play school sports. In February 2026 the Colorado High School Activities Association was asked how many transgender athletes compete in its sanctioned events. Its answer: “Due to privacy laws, this information is neither shared with or received by CHSAA.”

How to vote

Colorado votes by mail. Your ballot must arrive by 7 p.m.

County clerks send a ballot packet to every active registered voter by Friday, October 9, 2026. Drop boxes open October 12 and stay open through Election Day.

A ballot counts only if it is in the county clerk’s hands by 7:00 p.m. on November 3. A postmark is not enough.

Register by October 26 to get your ballot in the mail. After that you can still register and vote in person at a Voter Service and Polling Center, open from October 19 through Election Day.

Check your registration at GoVoteColorado.gov

Where to volunteer or donate

To volunteer or donate, go to Families Not Politics.

Families Not Politics is the registered issue committee opposing both measures. It was filed with the Colorado Secretary of State on February 10, 2026 and is led by One Colorado. If you want to volunteer, donate or get involved today, go to them.

One Colorado, which leads Families Not Politics Check your voter registration

Where to go next

Sources

Every claim above, at its source.

We quote the filed text and the state’s own records. What we could not verify, we left out.