In the United States, carrying a concealed weapon (CCW, also known as concealed carry) is the legal authorization for private citizens to carry a handgun or other weapons in public in a concealed manner, either on the person or in close proximity to the person. In some states, it is sufficient to be a resident or permanent resident (greencard holder). Under current federal legal precedent, it is constitutional under the Second Amendment for states to have concealed carry licensing that permits concealed carried weapons, or even not to require any permits for concealed carry weapons; for example, any legal gun owner in the state of Vermont may carry concealed weapons with no permitting required. It is likewise constitutional under the Second Amendment for states to have laws that prohibit concealed carried weapons, although only two states have done so. Laws governing concealed carried weapons vary from state to state. Some states restrict concealed carried weapons to a single handgun, whereas others permit multiple handguns or martial arts weapons to be carried.

Various states give different terms for licenses or permits to carry a concealed firearm, such as a Concealed Handgun License/Permit (CHL/CHP), Concealed (Defensive/Deadly) Weapon Permit/License (CDWL/CWP/CWL), Concealed Carry Permit/License (CCP/CCL), License To Carry (Firearms) (LTC/LTCF), Carry of Concealed Deadly Weapon license (CCDW), and similar. Many states that issue licenses to carry a concealed handgun also allow the practice of open carry by the license holder, and another 31 states allow open carry without any license.

Although the current trend towards adopting concealed carry laws has been met with opposition, no state which has adopted a "Shall-Issue" concealed carry law has reversed its decision. As of February 2008, 48 US states allow some form of concealed carry (though nine of them have discretionary "may-issue" policies, a few of these being effectively "no-issue" in practice) and all but six provide for some variant on non-concealed "open-carry". The states of Wisconsin and Illinois, and the District of Columbia do not have any form of concealed-carry licensing; Wisconsin allows for open carry in most situations, while Illinois only allows it in rural areas subject to county restriction.

On March 19, 2009, a federal judge ordered a temporary restraining order blocking the implementation of the rule allowing concealed carry permit holders to carry firearms concealed within National Park Service lands within states where their permits are valid, based upon environmental concerns, in response to concerns by the Brady Campaign to Prevent Gun Violence, the National Parks Conservation Association, and the Coalition of National Park Service Retirees. On May 22, 2009 President Obama signed a law (HR 627) that will prohibit the Secretary of the Interior from enacting or enforcing any regulations that restrict possession of firearms in National Parks or Wildlife Refuges, as long as the person complies with laws of the state in which the unit is found.