JOINT RELEASE: SB25-003 Goes Into Effect
DENVER, CO – SB25-003, sponsored by Senators Tom Sullivan, D-Centennial, and Julie Gonzales, D-Denver, and Speaker Pro Tempore Andy Boesenecker, D-Fort Collins, and Representative Meg Froelich, D-Englewood, goes into effect August 1, 2026.
The law requires a permit and firearm safety training to purchase high-powered firearms that accept detachable magazines. It also prohibits the purchase and sale of all rapid fire conversion devices, like bump stocks and binary triggers.
“High-capacity magazines are what put the ‘mass’ into mass shootings, which is why over a decade ago Colorado Democrats passed legislation to prohibit magazines that hold over 15 rounds of ammunition,” said Sullivan. “This law further enforces that ban. It will save lives and increase safety for all Coloradans. The people of Colorado have mandated that we do something about the public health crisis that is gun violence, so that’s exactly what we're doing.”
“As gun violence continues to devastate communities across Colorado, Colorado Democrats are again taking action to prevent future tragedies,” said Boesenecker. “When semiautomatic weapons and high-capacity magazines get into the wrong hands, it presents a major threat to the health and safety of our communities. With this law going into effect soon, we’re taking another step to prevent senseless violence in our communities and save countless lives.”
“Gun violence continues to have devastating effects on Colorado communities, and we must do more to protect lives,” said Gonzales. “The firearm industry’s profits come, time and again, at the expense of public safety. Something has to change. Senate Bill 3 is about holding firearm manufacturers to account and enforcing the law we have had on the books for more than a decade. I’m honored to join Senator Sullivan on this legislation and in his work to reduce gun violence in Colorado.”
“This gun violence prevention law answers the call to action from our neighbors and will save lives,” said Froelich. “We know that semiautomatic weapons become especially deadly when they are paired with high-capacity magazines, which is why Colorado Democrats passed a 2013 law to prohibit those high-capacity magazines. We’ve raised a generation on lockdown drills, and 1 in 15 people have experienced a mass shooting. This law will help save lives and prevent more Coloradans from having to go through the pain of losing a loved one to senseless gun violence.”
"Colorado is proving that passing a strong gun safety law is only the beginning. Successful implementation is what transforms policy on paper into lives saved,” said Justin Wagner, senior vice president of law and policy at Everytown for Gun Safety. “As Senate Bill 3 takes effect, Colorado has built a clear, workable system that helps ensure the people purchasing high-powered firearms have completed safety training and passed a thorough background check. This law gives states across the country a roadmap for implementing innovative policies that keep communities safe while providing clarity for responsible gun purchasers, retailers, and law enforcement.”
“Students have grown up practicing active shooter drills while watching communities across Colorado be forever changed by preventable gun violence,” said Norah Krause, leader with Colorado Students Demand Action. “With Senate Bill 3 now in effect, our state is putting stronger safeguards in place to help keep the most lethal firearms out of dangerous hands. Young people fought for this law because we refuse to accept gun violence as a normal part of growing up, and we’ll keep organizing until every student can learn without fear.”
“This law is taking effect because survivors, volunteers, students, and lawmakers refused to accept that mass shootings are inevitable,” said Kathy Hagen, lead with the Colorado chapter of Moms Demand Action. “Colorado families deserve to know that there are meaningful safeguards in place before someone can purchase the firearms most often used in our country's deadliest mass shootings. This marks another important step toward a safer Colorado.”
SB25-003 requires a person who wants to purchase certain specified semiautomatic firearms to first obtain a permit, which requires undergoing a background check and completing a firearm safety training course that includes instruction on safe usage and storage of these firearms, federal and state firearm laws, and a demonstrated ability to safely handle these devices.
The law does not impact the sale of manual-action shotguns, lever- or bolt-action rifles, commonly used hunting rifles, semiautomatic firearms that have fixed magazines, or any revolvers or recoil operated handguns, which make up well over 90 percent of the handgun market. While SB25-003 requires a permit to purchase gas-operated semiautomatic pistols that accept detachable magazines, those types of pistols are relatively uncommon. The law does not impact possession of currently-owned specified semiautomatic firearms.
Colorado Parks and Wildlife has published a guide on how to purchase a specified semiautomatic firearm in accordance with the new law. This resource includes guidance, prepared by the Department of Revenue, of which makes and models fall within the law’s definition of "specified semiautomatic firearms.
In response to the 2013 Aurora theater shooting, Colorado Democrats passed legislation that prohibited the sale and transfer of magazines that hold more than 15 rounds of ammunition. Semiautomatic weapons and high-capacity magazines have been used in numerous mass shootings in Colorado, including the 2021 Boulder King Soopers shooting, the 2022 Club Q shooting, and the Columbine High School massacre. SB25-003 enforces Colorado’s existing high-capacity magazine ban by adding safeguards prior to the purchase of the types of semiautomatic weapons that are most lethal when paired with a high-capacity magazine.
SB25-003 was signed into law by Governor Polis on April 10, 2025.