Colorado Now Checks Every Ammunition Buyer's ID and Turns Away Adults Under 21

How old do you have to be to buy a box of shotgun shells in Colorado?

Since July 1, 2026, the answer is 21. And you have to show a photo ID to prove it, whether you are 21 or 71.

Start with where things stood. In 2023, Colorado raised the minimum age to buy a gun to 21. HB25-1133 applies the same age limit to ammunition.

1. It sets the age at 21. A store may not sell ammunition to anyone under 21.
2. It checks everyone's ID. Before any in-person sale, the store must check the buyer's age "by requiring the purchaser to produce a valid government-issued photo identification." The law makes no exception for buyers who are obviously older. A 70-year-old rancher buying deer rounds shows his driver's license like everyone else.
3. It puts ammunition behind the counter. Stores may not display ammunition where a customer can pick it up without help from an employee. Picture how some pharmacies keep cold medicine behind the counter. Colorado now treats ammunition the same way.
4. It follows the box to your door. A seller who ships ammunition must use a delivery service that checks age. The driver must look at a government photo ID at the door and get a signed receipt. The law covers sellers outside Colorado who ship into the state.
5. It penalizes the seller. Breaking these rules is a civil infraction, like a traffic ticket, for the first offense. A second offense is a misdemeanor, a minor crime.

The law leaves out .22 caliber rimfire ammunition, the small rounds many people learn to shoot with. It also leaves out wholesale sales between businesses.

The list of exceptions tells you a lot about the law.

• Members and veterans of the U.S. military or the Colorado National Guard, with a military ID.
• Young adults who have passed a state hunter education course.
• Young adults buying at a shooting range, only for use at that range.
• On-duty police officers.
• A young adult who is protected by a court's protection order, such as a restraining order against a stalker or abuser. That person must bring a copy of the order to the store and confirm it is still in effect.

Read that last one again. A 19-year-old woman being stalked can buy ammunition to protect herself, but only after a judge has signed an order and she carries a copy of it to the store. Her right to defend herself starts with the paperwork.

That list shows what the law is really about. The state does trust some adults under 21 with ammunition. It trusts them as soon as they carry the right document: a military ID, a hunter education card, or a court order. So an 18-year-old's right to buy ammunition now depends on which government office has vouched for him.

Every one of those exceptions also applies only in the store, when the buyer leaves with the ammunition in hand. Deliveries always require a buyer who is 21 or older. A 20-year-old Army veteran on a ranch two hours from the nearest store can buy at the counter, but he cannot have the same box shipped to his door.

The law lets stores keep selling to 18-to-20-year-olds who were "born on or before January 28, 2007." That rule ends on January 28, 2028.

Do the math. Someone born on January 28, 2007 turned 18 on January 28, 2025, the day HB25-1133 was introduced. The youngest person in that group turns 21 on the day the rule ends. So the rule never tightens anything. It lets every adult who could legally buy ammunition on the day the bill was filed keep buying it. Everyone who turned 18 after that day cannot. Two siblings born a year apart can land on opposite sides of the line.

Supporters make a fair case. States set age limits all the time, for alcohol, tobacco, and renting a car. Supporters point to research on brain development in young adults and to how many gun crimes are committed by people under 21. The federal appeals court that covers Colorado, called the Tenth Circuit, cited that same research in November 2024 when it upheld Colorado's 2023 law raising the gun-buying age to 21.

That is a fair point about alcohol and cars. Those products have one thing in common: none of them is named in the Bill of Rights. The right to keep and bear arms is. At 18, a young man in Colorado registers for the military draft, votes, serves on juries, and signs contracts. The Constitution treats him as an adult. HB25-1133 treats him as an adult for everything except the one right the Second Amendment names, and even there it makes an exception if the government trained him first.

In that November 2024 case, Rocky Mountain Gun Owners v. Polis, the Tenth Circuit said that rules about the sale of guns, such as a minimum age to buy, are generally allowed under the Second Amendment. A federal judge then threw out the challenge to Colorado's 2023 law in June 2025.

Now look at the order of Colorado's laws: the age to buy a gun in 2023, the age to buy ammunition in 2025, and a permit to buy a semiautomatic rifle in 2025. Each one is written as a rule about buying and selling. The courts have said that is where states have the most room, so that is where Colorado keeps adding limits.

For now, that approach is holding. On June 30, 2026, the U.S. Supreme Court declined to hear a challenge to Florida's ban on gun sales to people under 21. As of September 24, 2026, we found no lawsuit filed against HB25-1133.

HB25-1133 passed the House 38-27 and the Senate 19-16. The House accepted the Senate's changes 43-20 and passed the final version 38-25. Every lead sponsor was a Democrat: Representatives Monica Duran and Lindsay Gilchrist and Senators Judith Amabile and Cathy Kipp. Governor Jared Polis signed it April 18, 2025.

This bill did not carry a "safety clause," the provision Colorado lawmakers use to make a law take effect right away and block citizens from putting it on the ballot. So voters could have gathered signatures to force a public vote. No one did, and the law took effect on schedule.

In Colorado, a 20-year-old can register for the draft, serve on a jury, and sign a mortgage. To buy a box of rifle rounds, he needs a military ID, a hunter education card, or a court order saying someone is trying to hurt him.

This is our read of the law. We encourage you to read it yourself and reach your own conclusions.