How Much Jail Time for Illegal Gun Possession?

Illegal gun possession most often carries up to 15 years in federal prison, but the jail time for illegal gun possession can range from a few months in a county jail to a mandatory life sentence, depending on who was carrying, what they were carrying, and what else was going on at the time. The single most common federal charge (possessing a firearm while in a prohibited category, such as having a prior felony) tops out at 15 years. Add a drug deal, a violent crime, or a machine gun to the picture and the numbers climb fast, often into territory where the judge has no discretion to go lower.

The 15-Year Federal Maximum for Prohibited Persons

Federal law bars several categories of people from possessing any firearm or ammunition, including anyone convicted of a crime punishable by more than a year in prison, fugitives, unlawful drug users, people committed for mental illness, certain noncitizens, and people under qualifying domestic violence restraining orders or convictions. Possession by anyone in these categories carries up to 15 years in prison and a fine of up to $250,000.¹² That maximum was raised from 10 years by the Bipartisan Safer Communities Act in 2022, so older references to a 10-year ceiling are out of date.

Fifteen years is the ceiling for a first offense. For repeat offenders, it becomes the floor. The Armed Career Criminal Act imposes a mandatory minimum of 15 years for anyone caught with a firearm who already has three or more prior convictions for violent felonies or serious drug offenses.¹ Judges cannot go below that floor and cannot substitute probation.

When a Gun Is Tied to Another Crime

The biggest sentences come when a firearm is connected to a drug trafficking crime or a federal violent crime. Under 18 USC 924(c), a separate set of mandatory minimums attaches to the gun, and they must run consecutively to the sentence for the underlying crime.³ You serve them back-to-back, not at the same time. The minimums depend on how the gun was used:

Possessing a firearm during the crime: at least 5 years
Brandishing the weapon: at least 7 years
Firing the weapon: at least 10 years
Using a short-barreled rifle, short-barreled shotgun, or semiautomatic assault weapon: at least 10 years
Using a machine gun, destructive device, or silencer: at least 30 years

A second conviction under this provision raises the floor to 25 years. If that second offense involves a machine gun or silencer, the sentence is life in prison.¹ Probation is not available, and no part of the sentence can overlap with any other prison term. This is where federal gun cases produce the headline sentences. A defendant convicted of a drug trafficking charge carrying 10 years, plus a first-time 924(c) count, faces at least 15 years combined before any other enhancement enters the calculation.

Penalties Tied to the Weapon Itself

Unregistered NFA Firearms

The National Firearms Act covers machine guns, short-barreled rifles, short-barreled shotguns, silencers, and destructive devices.⁴ Legally owning one requires registering it through the ATF and paying a $200 tax. Possessing an unregistered NFA firearm is punishable by up to 10 years in prison and a $10,000 fine.⁵ Civilian ownership of machine guns manufactured after May 19, 1986, is banned outright, so no registration is available for a post-1986 machine gun.

Altered or Obliterated Serial Numbers

Possessing a firearm whose serial number has been removed, scratched off, or changed carries up to five years in federal prison, provided the gun has at some point moved across state lines.⁶¹ Prosecutors and judges tend to read an obliterated serial as evidence the gun was intended for criminal use, which affects both charging decisions and sentencing.

Straw Purchases

Buying a gun on behalf of someone who cannot legally purchase one is a straw purchase, and the Bipartisan Safer Communities Act created a dedicated statute for it. The penalty is up to 15 years in prison and a $250,000 fine. If the buyer knows or has reason to believe the gun will be used in a felony, an act of terrorism, or drug trafficking, the maximum jumps to 25 years.⁷ Before this statute existed, straw purchases were typically charged as lying on a federal firearms form and topped out at 10 years.

State Penalties for Carrying Without a Permit

Most illegal-carry cases never see a federal courtroom. Carrying a handgun in public without the required permit is one of the most frequently charged firearms offenses at the state level. Penalties run from misdemeanors carrying a few months in jail to felonies with multi-year prison terms, depending on the state and the defendant’s record. Some states impose mandatory minimums for unlicensed carry, often in the three-to-five-year range, particularly in urban areas or for repeat offenders.

The map has shifted. Roughly 29 states now allow permitless concealed carry for anyone who can legally own a firearm, so conduct that was criminal a few years ago is now legal in over half the country. In states that still require permits, the consequences for violating them can be steep, and reciprocity between states is patchy. Traveling armed across a state line without checking the destination’s law is one of the most common ways otherwise law-abiding gun owners end up charged.

What Actually Drives the Sentence

The statutes set the ceiling and, for mandatory minimums, the floor. Where a sentence lands inside that window turns on a handful of factors.

Criminal History

This is the single biggest driver. Federal sentencing guidelines assign points based on prior convictions, and the resulting category can easily double or triple the recommended range for the same offense. A first-time offender convicted of felon-in-possession might receive two to four years. The same charge for someone with an extensive record can land in the 10-to-15-year range even without triggering the Armed Career Criminal Act.

Connection to Other Criminal Activity

A gun charge from a traffic stop hits differently than one arising from a drug deal or a robbery. When prosecutors tie the firearm to another crime, the 924(c) minimums come into play and the math changes entirely. Even without a formal 924(c) count, federal guidelines allow judges to increase the offense level when the weapon was connected to other criminal conduct.

Type and Number of Weapons

One handgun is treated very differently from an arsenal. Multiple firearms, military-style weapons, or NFA items suggest trafficking rather than simple possession, and the guidelines increase the offense level accordingly.

You Don’t Have to Be Holding It

A common misconception is that possession requires the gun to be in your hand. Federal law recognizes two forms. Actual possession means the weapon is on your person or within arm’s reach. Constructive possession means you have both the ability and the intention to control the weapon, even if it’s somewhere else.⁸ A gun in the glove compartment of your car, in a bedroom you use, or in a storage unit you rent can all support a possession charge and the full sentencing exposure that comes with it.

Federal vs. State Prosecution

Whether a case is filed in state or federal court has enormous practical consequences for sentence length. Most routine cases (unlicensed carry, possession after a state felony) are prosecuted in state court. Federal prosecutors typically step in when the case involves interstate activity, a federally prohibited person, an NFA weapon, or a connection to drug trafficking or organized crime. The ATF investigates most federal firearms cases.⁹

Federal prosecution generally means harsher outcomes. Federal sentences tend to be longer, there is no parole in the federal system, and defendants must serve at least 85% of the sentence imposed. Mandatory minimums are more common. Both state and federal prosecutors can charge the same conduct under the separate sovereigns doctrine, which the Supreme Court has repeatedly held does not violate double jeopardy. Dual prosecution is uncommon for low-level offenses but happens in serious cases where both systems have an interest in the outcome.

What Comes After the Sentence

Prison time is not the end of the penalty. Federal felony fines can reach $250,000, and state fines add their own range from several thousand to tens of thousands of dollars.² After release, federal defendants typically serve a term of supervised release with strict conditions: probation officer meetings, drug testing, travel restrictions, sometimes electronic monitoring. Violating any condition can send you back to prison to serve additional time on top of the original sentence.

The most permanent consequence is the lifetime federal ban on possessing firearms or ammunition that follows any felony conviction, even one unrelated to guns. A felony drug case, a fraud case, or any other crime punishable by more than a year in prison triggers the same prohibition.⁶ Once that ban attaches, a subsequent gun charge no longer sits in the misdemeanor or unlicensed-carry lane; it becomes the 15-year prohibited-person felony described at the top of this article, and the cycle escalates from there.

1
Office of the Law Revision Counsel. 18 USC 924 – Penalties
2
Office of the Law Revision Counsel. 18 USC 3571 – Sentence of Fine
3
United States Sentencing Commission. Section 924(c) Firearms
4
Bureau of Alcohol, Tobacco, Firearms and Explosives. National Firearms Act
5
Office of the Law Revision Counsel. 26 USC 5871 – Penalties
6
Office of the Law Revision Counsel. 18 USC 922 – Unlawful Acts
7
Office of the Law Revision Counsel. 18 USC 932 – Straw Purchasing of Firearms
8
United States District Court District of Massachusetts. Possession of a Firearm or Ammunition in or Affecting Commerce by a Convicted Felon
9
Bureau of Alcohol, Tobacco, Firearms and Explosives. Identify Prohibited Persons