Last Updated: Aug 07, 2026
Colorado is one of the strictest states in the country for private gun sales. Every private transfer here requires a background check through a licensed FFL dealer and the Colorado Bureau of Investigation (CBI), a mandatory 3-day waiting period, and a 15-round magazine capacity limit. As of August 1, 2026, a new law (SB 25-003) also requires buyers of most semi-automatic rifles and shotguns with detachable magazines — and gas-operated semi-automatic handguns with detachable magazines — to first complete a state-approved safety course and obtain a sheriff-issued eligibility card. Most traditional pistols are unaffected. This Bill of Sale documents the agreed price and firearm details before you visit the dealer — protecting you if the buyer backs out or fails the background check.
📄 Colorado Firearm Form Draft:
The Paperwork Beyond This Page
Colorado's background check, waiting period, and 2026 safety-course rules are covered above. What's not covered here — because it's the same everywhere — is the mechanics of filling out and signing the Bill of Sale itself.
See our nationwide Step-by-Step Firearm Bill of Sale Guide for that walkthrough.
📋 Colorado Legal Essentials for Private Sellers
1. Every Sale Requires a Dealer, a Check, and a Wait
Since 2013, Colorado has required background checks on nearly all private firearm transfers under C.R.S. § 18-12-112. Both parties must go to a licensed FFL, who runs the check through the Colorado Bureau of Investigation (CBI). Once approved, a mandatory 3-day (72-hour) waiting period applies before the buyer can take possession, and the transfer must be completed within 30 days of CBI approval.
⚠️ Don't assume a quick handshake deal is legal just because you know the buyer — unless they qualify for the narrow immediate-family exemption, skipping the FFL and CBI check is a criminal offense.
2. The Family Exemption Has a Sharp Edge: In-Laws Don't Count
Colorado exempts bona fide gifts or loans between immediate family members from the background check requirement — a broad list that includes spouses, parents, children, siblings, grandparents, grandchildren, nieces, nephews, first cousins, aunts, and uncles. In-laws are explicitly excluded.
⚠️ Don't assume your brother-in-law or son-in-law qualifies for the family exemption — they don't, and treating them as if they do means skipping a legally required background check.
3. A New Safety-Course Requirement Started August 1, 2026
SB 25-003 now requires a state-approved safety course and a sheriff-issued eligibility card before someone can buy most semi-automatic rifles or shotguns with a detachable magazine, or a gas-operated semi-automatic handgun with a detachable magazine. The good news for most sellers: recoil-operated pistols — the design behind the large majority of handguns on the market — are not covered by this requirement.
⚠️ Don't assume this new rule applies to every semi-automatic firearm you might sell — check whether your specific firearm falls into a covered category before assuming the buyer needs the eligibility card.
4. The 15-Round Magazine Limit Applies to Transfers, Not Just New Sales
Colorado has banned the sale or transfer of magazines over 15 rounds since 2013. Magazines you owned before July 1, 2013 are grandfathered for your own possession, but that grandfathering doesn't carry over to a sale — transferring a pre-2013 large-capacity magazine to someone else is still illegal.
⚠️ Don't include an old, legally-owned high-capacity magazine as a 'bonus' with a firearm sale — grandfathered possession rights are personal to you and don't transfer with the gun.
5. There's No Registry, But There Is a Paper Trail
Colorado law bars local governments from maintaining a firearm registry, and CBI's background-check records function as transaction logs rather than an ownership database. Still, every FFL-processed sale leaves an official record with the dealer and CBI — a private Bill of Sale remains your own copy of the terms and condition of the firearm at the time of sale.
⚠️ Don't assume 'no registry' means 'no record' — the FFL and CBI both retain transaction records, so your own documentation should match what was reported.
This information reflects publicly available Colorado statutes and enforcement practices. Colorado's firearm laws have changed significantly in recent years and some provisions remain subject to litigation — always verify the latest rules and consult a qualified attorney.
Colorado Firearm Transfer FAQ
Are background checks required for private sales in Colorado?
Yes — Colorado has required background checks for all private transfers since 2013. Both parties must visit a licensed FFL dealer who runs the check through the Colorado Bureau of Investigation (CBI). The dealer can charge up to $10 for the CBI fee plus a processing fee. Once approved, the transfer must be completed within 30 days. Source: C.R.S. § 18-12-112
Why do I need a Bill of Sale if the FFL handles the paperwork?
The dealer's records protect the state — not you. This Bill of Sale is your private contract that documents the agreed price and condition of the firearm at the time of transfer, giving you a clear record of what was agreed and when.
What is the new semi-automatic firearm safety requirement in 2026?
As of August 1, 2026, Colorado law (SB 25-003) requires buyers to complete a state-approved firearms safety course and obtain a sheriff-issued eligibility card before purchasing most semi-automatic rifles or shotguns with a detachable magazine, or a gas-operated semi-automatic handgun with a detachable magazine. Most traditional pistols — recoil-operated models like the majority of Glocks, 1911s, and similar platforms — are not covered. If you're selling a firearm in one of the covered categories, verify the buyer's eligibility card before visiting the dealer. Source: SB 25-003
Does Colorado have a waiting period?
Yes. Colorado has a mandatory 3-day (72-hour) waiting period between the CBI background check approval and the physical transfer of the firearm. This applies to all private transfers processed through an FFL. Source: HB23-1219
What is the minimum age for private gun sales in Colorado?
The minimum age for purchasing any firearm in Colorado is 21 — a change from the previous federal-aligned standard of 18 for long guns. This is currently in effect, though it remains subject to ongoing federal court challenges; confirm current status before relying on it. Separately, as of July 1, 2026, buyers must also be at least 21 to purchase rifle and shotgun ammunition. Source: SB23-169
What is the magazine capacity limit in Colorado?
Colorado prohibits the sale or transfer of magazines holding more than 15 rounds. Magazines owned before July 1, 2013, are grandfathered for possession, but their private transfer or sale is strictly illegal. Source: C.R.S. § 18-12-302
Can I sell to a family member without a background check?
Yes, but only to immediate family, defined broadly to include spouses, parents, children, siblings, grandparents, grandchildren, nieces, nephews, first cousins, aunts, and uncles. Critically, in-laws are excluded from this exemption — a transfer to a brother-in-law requires a full CBI check like any other private sale. Source: C.R.S. § 18-12-112
Can I sell my gun at a Colorado gun show without a background check?
No. Universal background checks apply at gun shows just as they do everywhere else in the state — there is no 'gun show loophole' in Colorado. Always process the sale through an on-site or nearby FFL dealer.
Who is prohibited from buying a firearm in Colorado?
Prohibited persons include convicted felons and those subject to domestic violence protective orders, among other federal and state disqualifiers. Colorado also uses Extreme Risk Protection Orders (ERPO), or 'Red Flag' orders, which can temporarily remove firearm access from someone deemed a danger. Source: Colorado Judicial Branch – Extreme Risk Protection Orders
Is there a state gun registry in Colorado?
No. State law prohibits local governments from maintaining a firearm registry. CBI records are individual transaction logs used for background checks, not a searchable ownership registry. Your Bill of Sale remains your only private proof of when ownership changed hands. Source: C.R.S. § 29-11.7-102