Overview

Missouri does not have statewide preemption, so local ordinances may impose additional restrictions. Open carry is legal, but concealed carry of certain knives is restricted. There is no general blade length restriction. All common knife types are legal to own and carry.

Quick Legal Facts

Statewide PreemptionNo.
Critical DimensionsFour (4) inches or less legal blade length for a pocketknife which can be carried concealed.
MinorsNo knife restrictions.

Carry Laws & Blade Length

Concealed CarryRestricted

Under § 571.030(1)(1), it is unlawful to carry concealed a knife, firearm, or other weapon readily capable of lethal use into any area where firearms are restricted under § 571.107. An 'ordinary pocketknife' (folding knife with blade 4 inches or less, per § 571.010(12)) is excluded from the statutory definition of 'knife' and may be carried concealed anywhere without restriction. Knives that do not qualify as ordinary pocketknives may be carried concealed in non-restricted locations without a permit (permitless carry framework effective January 1, 2017). Holders of a valid concealed carry permit are exempt from subdivisions (1), (8), and (10) of § 571.030(1), granting broader concealed carry rights.

Statute: 571.030, 571.010, 571.107

Blade Length LimitNone

No general statewide blade length limit for possession, open carry, or purchase. The 4-inch threshold in § 571.010(12) is definitional only: folding knives with blades of 4 inches or less qualify as 'ordinary pocketknives' and are excluded from the statutory 'knife' definition, exempting them from concealed carry restrictions. Blades over 4 inches are classified as 'knives' subject to location-based concealed carry restrictions under § 571.030. No statewide preemption; local ordinances may impose blade length limits (e.g., Ballwin restricts to 2.5 inches).

Statute: 571.010, 571.030

Knife Type Legality

Knife TypeStatusDetails
Ballistic KnivesUnclear
Missouri statutes do not specifically mention or prohibit ballistic knives by name. They are not listed in § 571.020's prohibited weapons. A ballistic knife could potentially be classified as a 'projectile weapon' under § 571.010(16) (any weapon capable of expelling a projectile that could inflict serious physical injury by striking or piercing a person) rather than as a 'knife.' Federal law (15 U.S.C. § 1245) prohibits possession, manufacture, sale, and import of ballistic knives, which applies in Missouri regardless of state law.
Statute: 571.010, 571.020
Relevant Statutes(4)

Legal Disclaimer

This information is provided for general educational purposes and should not be construed as legal advice. Laws change frequently and local ordinances may impose additional restrictions beyond state law. Always verify with official state sources before making decisions about knife carry or ownership. KnifeInformer is not a law firm — consult a qualified attorney for specific legal questions.

All State Knife Laws