In the United States, open carry is shorthand terminology for "openly carrying a firearm in public", as distinguished from concealed carry, where firearms cannot be seen by the casual observer.
The practice of open carry, where gun owners openly carry firearms while they go about their daily business, has seen an increase in the U.S. in recent years. This has been marked by a number of organized events intended to increase the visibility of open carry and public awareness about the practice. Proponents of open carry point to history and statistics, noting that criminals usually conceal their weapons, a stark contrast to the law abiding citizens who proudly display their sidearms. Encouraged by groups like The Modern American Revolution, OpenCarry.org, GeorgiaCarry.org and some participants of the Free State Project, open carry has seen a revival in recent years, but it is not yet clear if this represents just a short-term trend.
The gun rights community has been mixed in its response. Alan Gottlieb of the Second Amendment Foundation and the NRA have been cautious in expressing support, while special-interest groups such as the aforementioned OpenCarry.org and GeorgiaCarry.org, and certain national groups such as the Gun Owners of America (GOA) have been more outspoken in favor of the practice.
A man openly carrying a handgun at a fast food restaurant in Eagle, Colorado.
The act of publicly carrying a firearm on one's person in plain sight.
Broadly defined as not being hidden from common observation; varies somewhat from state to state. Some states specify that open carry occurs when the weapon is "partially visible," while other jurisdictions require the weapon to be "fully visible" to be considered carried openly.
Definition varies from state to state. Depending on state law, a weapon may be considered "loaded" under one of the following criteria:
Only when a live round of ammunition is in the firing chamber of the weapon
When a magazine with ammunition is inserted into the firearm, regardless of whether or not a round is in the chamber
When a person has both the firearm and its ammunition in his or her possession, without regard as to whether or not a round is in the chamber or a magazine with ammunition is inserted into the firearm (most common legal definition in "gun-control" states)
In the context of open carry: the act of a state legislature passing laws which limit or eliminate the ability of local governments to regulate the possession or carrying of firearms.
Today in the United States, the laws vary from state to state regarding open carry of firearms. The categories are defined as follows:
Permissive open carry states
A state has passed full preemption of all firearms laws. They do not prohibit open carry for all non-prohibited citizens and do not require a permit or license to open carry. Open carry is lawful on foot and in a motor vehicle. It must be noted that while open carry may be legal in such jurisdictions per se, persons openly carrying firearms may be detained and cited by law enforcement officials for disorderly conduct or disturbing the peace in certain locations and circumstances where openly carrying could cause public alarm.
Licensed open carry states
A state has passed full preemption of all firearms laws. They permit open carry of a handgun to all non-prohibited citizens once they have been issued a permit or license. Open carry of a handgun is lawful on foot and in a motor vehicle. In practice however, some of these states that have May-Issue licensing laws can be regarded as Non-Permissive for open carry, as issuing authorities rarely or never grant licenses to ordinary citizens.
Anomalous open carry states
In these states, open carry of a handgun is generally lawful, but the state may lack preemption or there may be other significant restrictions. The limitations and/or lack of pre-emption may mean that certain areas of these states are, in their judicial system and law enforcement societies, not very friendly towards the practice, although this is not true in all of these states.
Non-permissive open carry states
In these states, open carry of a handgun is not lawful, or is only lawful under such a limited set of circumstances that public carry is effectively prohibited. Such limited circumstances may include when hunting, or while traveling to/from hunting locations, while on property controlled by the person carrying, or for lawful self-defense. Additionally, some states with May-Issue licensing laws are Non-Permissive when issuing authorities are highly restrictive in the issuance of licenses allowing open carry.
Rural open carry states
In these states, open carry is generally not prohibited only in unincorporated areas of counties where population densities are below statutorily-defined thresholds, and local authorities have enacted legislation to not prohibit open carry in such jurisdictions (California). As such, these states are also regarded as Non-Permissive open carry states.
Open carry legal in rural counties with local ordinances allowing open carry. Some of these counties issue a permit for open carry.
Open carry without a license permitted statewide, except in the City and County of Denver (where open carry is prohibited by local ordinances that pre-date Colorado's statewide pre-emption law).
Open carry with a valid pistol permit is legal statewide.
Connecticut is May-Issue according to state law, but Shall-Issue according to court precedence and in practice. While Connecticut's pistol permit law states that the issuing authority may-issue a pistol permit to a qualified individual, Connecticut law does not require applicants to show "good cause" for needing a pistol permit. As such, the state's courts have generally ruled that issuing authorities must grant pistol permits to qualified individuals who have passed a criminal and mental health background check and completed the required firearms safety training.
No permit or special license required.
Due to a "grandfathered" ordinance pre-dating state pre-emption, open carry not permitted in the City of Dover without a letter from the Chief of Police or a Concealed Deadly Weapon License.
The constitutionality of the general ban on open carry is currently being challenged in the Florida 4th District Court of Appeals case of Norman v. State
F.S. 790.25(3) states the provisions of ss. 790.053 [open carry ban] and 790.06 [concealed carry license] do not apply in the following instances, and, despite such sections, it is lawful for the following persons to own, possess, and lawfully use firearms and other weapons, ammunition, and supplies for lawful purposes. A few instances are listed below:
(h) A person engaged in fishing, camping, or lawful hunting or going to or returning from a fishing, camping, or lawful hunting expedition; (i) A person engaged in the business of manufacturing, repairing, or dealing in firearms, or the agent or representative of any such person while engaged in the lawful course of such business; (j) A person firing weapons for testing or target practice under safe conditions and in a safe place not prohibited by law or going to or from such place; (k) A person firing weapons in a safe and secure indoor range for testing and target practice; (l) A person traveling by private conveyance when the weapon is securely encased or in a public conveyance when the weapon is securely encased and not in the person’s manual possession; (m) A person while carrying a pistol unloaded and in a secure wrapper, concealed or otherwise, from the place of purchase to his or her home or place of business or to a place of repair or back to his or her home or place of business; (n) A person possessing arms at his or her home or place of business;
Licenses granted on a Shall Issue basis. Preemption law enacted in 2011.
Kansas HB 2578 voided all local carry laws as of July 1st 2014, Making Kansas a Permissive State.
Open carry is legal in Louisiana. Attorney General Opinion No. 78-0795 - The AG replies to two questions: "1. Is it legal to carry an exposed handgun?" and "2. Do Parishes and/or Municipalities have the power to regulate the carrying of exposed handguns?" The AG responds, "the carrying of an exposed handgun is not illegal, except as provided in LSA R.S. 14:95.1." And citing City of Shreveport V. Curry and City of Shreveport V. Bukhett, 357 S.2d 1078, (LA. 1978) the AG answers " It is the opinion of this office that the state statutes aforementioned have the purpose of establishing a general scheme to control weapons (handguns) and that a fair reading of those statutes show this would constitute an area in which the state has preempted the legislative control and has implicitly authorized the carrying of unconcealed weapons. Therefore, an ordinance enacted by a Parish and/or Municipality regulating the carrying of exposed handguns would be without effect as being in conflict with State Law.
Licenses are rarely issued to ordinary citizens.
Pistol permits are issued by local authorities on a May-Issue basis. Ability to obtain a pistol permit varies between localities. Pistol permits are valid statewide, regardless of where they were issued.
State law says: "A local unit of government shall not impose special taxation on, enact or enforce any ordinance or regulation pertaining to, or regulate in any other manner the ownership, registration, purchase, sale, transfer, transportation, or possession of pistols or other firearms, ammunition for pistols or other firearms, or components of pistols or other firearms, except as otherwise provided by federal law or a law of this state."
State preemption was passed taking effect in October of 2014 and a concealed carry license is necessary.
Licenses rarely granted to ordinary citizens.
State law does not preempt tribal laws on Native American reservations, except when traversing a reservation on a state-owned highway. Some tribes do not permit open carry, while some others may require a tribal permit for open carry.
Some rural counties issue permits for open carry (valid in the issuing county only)
Ohio is an open carry state. Open carry is not permitted in vehicles without a Concealed Handgun License. Local firearm laws were preempted in 2007.
Some more populous locations (Portland, Salem, etc.) have ordinances restricting open carry. Persons with concealed carry licenses are exempt from local open carry restrictions.
License to carry needed to open carry in a motor vehicle or in a city of the first class (pop over 1,000,000—currently only Philadelphia falls into this category) 
The open carry of modern handguns is prohibited but Texas law does not prohibit the open carry of long guns in public and provides for preemption of local government firearms law.
A license is required to openly carry a loaded firearm. No license necessary when the weapon is unloaded and exposed.
Open Carry is legal without a license, but to carry a handgun loaded in a vehicle one needs a concealed pistol license (CPL).
There are exceptions to the CPL for loaded in a vehicle requirement such as coming from or going to a lawful outdoor recreational activity. Openly carried pistol may be fully loaded. Washington State also has full state preemption.
Open carry has never been ruled out as a right under the Second Amendment of the U.S. Constitution by any court. In the majority opinion in the case of District of Columbia v. Heller (2008), Justice Antonin Scalia wrote concerning the entirety of the elements of the Second Amendment; "We find that they guarantee the individual right to possess and carry weapons in case of confrontation." However, Scalia continued, "Like most rights, the Second Amendment right is not unlimited. It is not a right to keep and carry any weapon whatsoever in any manner whatsoever and for whatever purpose."
Forty four states' constitutions recognize and secure the right to keep and bear arms in some form, and none of those prohibit the open carrying of firearms. Five state constitutions provide that the state legislature may regulate the manner of carrying or bearing arms, and advocates argue that none rule out open carry specifically. Nine states' constitutions indicate that the concealed carrying of firearms may be regulated and/or prohibited by the state legislature. Open carry advocates argue that, by exclusion, open carrying of arms may not be legislatively controlled in these states. But this is not settled law.
Section 1.7  of Kentucky's state constitution only empowers the state to enact laws prohibiting "concealed carry".
May 2, 1967 openly armed members of the Black Panther Party marched on the California State capitol in opposition to the then-proposed Mulford Act prohibiting the public carrying of loaded firearms. After the march in the state capitol building, the law was quickly enacted.
On June 16, 2000, the New Black Panther Party along with the National Black United Front and the New Black Muslim Movement protested the death sentencing conviction of Gary Graham, by openly carrying shotguns and rifles at the Texas Republican National convention in Houston, Texas.
In 2003, gun rights supporters in Ohio used a succession of Open Carry "Defense Walks" attempting to persuade the Governor to sign concealed carry legislation into law.
The legality of open carry of certain firearms in Virginia was reaffirmed after several 2004 incidents in which citizens openly carrying firearms were confronted by local law enforcement. The Virginia law prohibits the open carry, in certain localities, of any semiautomatic weapon holding more than 20 rounds or a shotgun that holds more than seven rounds, without a concealed carry permit.
In 2008, Brad Krause of West Allis, Wisconsin was arrested by police for alleged disorderly conduct while openly carrying a firearm while planting a tree on his property. A court later acquitted him of the disorderly conduct charge, observing in the process that in Wisconsin there is no law dealing with the issue of unconcealed weapons.
On September 11, 2008, Meleanie Hain had a handgun in plain view in a holster at her 5-year-old daughter's soccer game in Lebanon County, Pennsylvania, leading the county sheriff to revoke her weapons permit; a judge later reinstated it. About a year later, her estranged husband shot her dead in her home before killing himself. A second legal dispute with the sheriff continued after her death, but a federal judge dismissed that lawsuit on November 3, 2010.
On April 20, 2009, Wisconsin Attorney General J.B. Van Hollen issued a memorandum to district attorneys stating that open carry was legal and in and of itself does not warrant a charge of disorderly conduct. Milwaukee police chief Ed Flynn instructed his officers to take down anyone with a firearm, take the gun away, and then determine if the individual could legally carry it until they could make sure the situation is safe.
On May 31, 2009, Washington OpenCarry members held an open carry protest picnic at Silverdale's Waterfront Park, a county park. Attendees openly carried handguns in violation of posted regulations prohibiting firearms at the park. Washington state law allows the open carrying of firearms and specifically preempts local ordinances more restrictive than the state's, such as the one on the books for Kitsap county. Shortly after the protest Kitsap county commissioners voted to amend KCC10.12.080 to remove the language that banned firearms being carried in county parks. KCC10.12.080 Was amended on July 27, 2009 and as of May 31, 2012 most of the signs in the county still read that firearms are prohibited despite numerous attempts to get the county to update the signs. The amendment is listed as it reads in meeting minutes from July 2009
KCC10.12.080 Amendment: It is unlawful to shoot, fire or explode any firearm, firecracker, fireworks, torpedo or explosive of any kind or to carry any firearm or to shoot or fire any air gun, BB gun, bow and arrow or use any slingshot in any park, except the park director may authorize archery, slinging, fireworks and firing of small bore arms at designated times and places suitable for their use.
In July 2009, an open carry event organized by OpenCarry.org took place at Pacific Beach, San Diego, California, where citizens carrying unloaded pistols and revolvers were subjected to Section 12031(e) inspections of their firearms on demand by police officers. The officers were obviously well-briefed on the details of the law, which allowed Californians to openly carry only unloaded guns and allows carry of loaded magazines and speedloaders.
On August 11, 2009, William Kostric, a New Hampshire resident, Free State Project participant, and former member of We The People's Arizona Chapter, was seen carrying a loaded handgun openly in a holster while participating in a rally outside a town hall meeting hosted by PresidentBarack Obama at Portsmouth High School in New Hampshire. Kostric never attempted to enter the school, but rather stood some distance away on the private property of a nearby church, where he had permission to be. He held up a sign that read "It's Time to Water the Tree of Liberty!".
On August 16, 2009, "about a dozen" people were noted by police to be openly carrying firearms at a health care rally across the street from a Veterans of Foreign Wars Convention in the Phoenix Convention Center, where President Barack Obama was giving an address. While the Secret Service was "very much aware" of these individuals, Arizona law does not prohibit open carry. No crimes were committed by these protesters, and no arrests were made. In an interview with Fox News, commentator James Wesley Rawles characterized the Phoenix protesters as "merely exercising a pre-existing right". When he was asked about open carry, "but...without a permit?" Rawles opined, "We have a permit--it is called the Second Amendment."
In May 2010, Jesus C. Gonzalez was arrested and charged with homicide in a shooting which occurred while he was carrying a handgun. Gonzalez was involved in two prior arrests for disorderly conduct, based on his open carry practice. He filed a lawsuit claiming fourth and fourteenth amendment violations. His suit and appeal were both dismissed. Gonzalez was convicted on lesser charges, including reckless homicide.
The Starbucks coffee chain has been the target of several boycotts arranged by gun control groups to protest Starbucks' policy of allowing concealed and open carry weapons in stores, if allowed by local laws. A counter buycott was proposed for Valentines Day of 2012 to show support from gun owners for Starbucks, with the use of two dollar bills to represent Second Amendment rights. On September 17, 2013 Howard Schultz, the CEO of Starbucks, published a letter asking customers to refrain from bringing guns into his stores.
State laws on open carry vary widely. Six states, the Territory of the U.S. Virgin Islands and the District of Columbia fully prohibit the open carry of handguns. On the other side, twelve states permit open carry of a handgun without requiring the citizen to apply for any permit or license. Thirteen states require some form of permit (often the same permit as allows a person to carry concealed), and the remaining seventeen states, though not prohibiting the practice in general, do not preempt local laws or law enforcement policies, and/or have significant restrictions on the practice, such as prohibiting it within the boundaries of an incorporated urban area. Illinois allows open carry on private property only.
As of August, 2009, four states that currently restrict open carry as a remnant of the post-Civil war Reconstruction era (Texas, South Carolina, Oklahoma and Arkansas) are considering making it again legal. Bills were drafted in the Texas Legislature for the 2009 and 2011 sessions, backed by proponents such as OpenCarry.org, but did not make it to the floor.
On October 11, 2011, California Governor Jerry Brown signed into law that it would be a "misdemeanor to openly carry an exposed and unloaded handgun in public or in a vehicle." This does not apply to the open carry of rifles or long guns or persons in rural areas where permitted by ordinance.
On November 1, 2011, Wisconsin codified open carry and recognized its legality by adding a sub section to its Disorderly Conduct statute (947.01). Subsection 2 reads "Unless other facts and circumstances that indicate a criminal or malicious intent on the part of the person apply, a person is not in violation of, and may not be charged with a violation of, this section for loading, carrying, or going armed with a firearm, without regard to whether the firearm is loaded or is concealed or openly carried."
2012 May 15: Gov. Mary Fallin signed Senate Bill 1733, the Oklahoma Self Defense Act, which will allow people with Oklahoma concealed weapons permits to open carry if they so choose. The law took effect in November, 2012. "Under the measure, businesses may continue to prohibit firearms to be carried on their premises. SB 1733 prohibits carrying firearms on properties owned or leased by the city, state or federal government, at corrections facilities, in schools or college campuses, liquor stores and at sports arenas during sporting events."
The Federal Gun Free School Zones Act limits where a person may legally carry a firearm by generally prohibiting carry within one-thousand (1000) feet of the property-line of any K-12 school in the nation with private property excluded. A State-issued permit to carry may exempt a person from this restriction depending on the laws of the State, and most issuing States qualify for this exception. However, according to BATFE the exception in Federal law is only applicable to permit holders while in the State that physically issued their permit, and does not exempt people with out-of-state permits, even when their permit is recognized through State reciprocity agreements. BATFE letter explaining reciprocity of CCW permit holders and how it applies to Gun-Free School Zones.
In a 1995 Supreme Court case, the Act was declared unconstitutional. "The Court today properly concludes that the Commerce Clause does not grant Congress the authority to prohibit gun possession within 1,000 feet of a school, as it attempted to do in the Gun-Free School Zones Act of 1990, Pub. L. 101-647, 104 Stat. 4844." 
The law was reenacted in the slightly different form, in 1996.
^The Associated Press (February 28, 2010). "Gun supporters cheer Starbucks policy". Retrieved 2013-03-05. "Even in some "open carry" states, businesses are allowed to ban guns in their stores. And some have, creating political confrontations with gun owners. But Starbucks, the largest chain targeted, has refused to take the bait, saying in a statement this month that it follows state and local laws and has its own safety measures in its stores."
^O'Connell, Vanessa; Jargon, Julie (2010-03-04). "Starbucks, Other Retailers Dragged Into Gun-Control Dispute - WSJ.com". The Wall Street Journal. Retrieved 2010-03-11. "The "open carry" movement, in which gun owners carry unconcealed handguns as they go about their everyday business, is loosely organized around the country but has been gaining traction in recent months. Gun-control advocates have been pushing to quash the movement, including by petitioning the Starbucks coffee chain to ban guns on its premises. Anti-gun activists gathered at the original Starbucks in Seattle to push retailers like the coffee chain to ban customers from openly carrying guns, WSJ's Nick Wingfield reports. Businesses have the final say on their property. But the ones that don't opt to ban guns—such as Starbucks—have become parade grounds of sorts for open-carry advocates."
^"Gun-rights activists to descend on downtown Palo Alto - San Jose Mercury News". Retrieved 2010-03-11. "Today, a group of gun-rights advocates will exercise their Second Amendment rights by congregating in the plaza with unloaded firearms in plain view. Bay Area members of the national "open carry" movement said they chose the city in part because it is one of the few in the state that has a municipal ban on gun possession. Don't expect any '60s-style confrontations with authorities, however. Palo Alto officials said Friday they will not attempt to enforce the city's ordinance, since it is superseded by state law allowing people to carry guns openly as long as they're not loaded. "We're not going to try to fight state law on this," said Palo Alto police Lt. Sandra Brown. "We're just going to let it happen.""
^"Illinois", OpenCarry.org. Retrieved May 27, 2014. "Open carry is clearly prohibited except in unincorporated areas where the county has not made open carry illegal. Additionally, note that open carry is prohibited inside a vehicle even when in unincorporated areas. Further, a recent review of Illinois statutes indicates that even open carry on foot in unincorporated areas may also be unlawful, and so in an abundance of caution, we classify Illinois as a state banning open carry entirely."
^"Open Carrying in Illinois", Law Center to Prevent Gun Violence. Retrieved May 27, 2014. "Thus, while a person – whether a concealed carry licensee or not – is prohibited from knowingly carrying a fully unconcealed handgun in public, a concealed carry licensee may lawfully carry a partially exposed handgun."
^"The Morning Journal - Armed and shopping in Vermilion Ohio". Retrieved 2010-03-09. "About 70 people, who want a concealed-carry bill passed by the Ohio Legislature signed into law, showed up yesterday with pistols at their sides for a Vermilion open carry shopping day, which was organized by Ohioans For Concealed Carry."
^"Guns Worn In Open Legal, But Alarm Va. (washingtonpost.com)". The Washington Post. 2004-07-15. Retrieved 2010-03-15. "Perez said an officer spoke with the men, then took their guns and charged them with possession of a firearm in a public place. Virginia law 18.2-287.4 expressly prohibits "carrying loaded firearms in public areas. But the second paragraph of the law defines firearms only as any semiautomatic weapon that holds more than 20 rounds or a shotgun that holds more than seven rounds -- assault rifles, mostly, Van Cleave said. Regular six-shooters or pistols with nine- or 10-shot magazines are not "firearms" under this Virginia law."
^"West Allis man not guilty in open carry gun case - JSOnline". Retrieved 2010-03-15. "Municipal Judge Paul Murphy said he had reviewed several state statutes and court cases related to the right to keep and bear arms. "There being no law whatsoever dealing with the issue of an unconcealed weapon or the so-called open carry is why we're here today," Murphy said. In the end, he determined Krause's actions did not rise to disorderly conduct and found him not guilty."
^"Police Stop Man For Carrying Gun Out In Open". Retrieved 2010-03-10. "He said many departments are asking questions about how to deal with people openly carrying firearms. He said it may end up being a community-by-community, case-by-case issue fraught with the potential for danger. "Now, with open carry, which is legal, there may be no training. I could hand you my handgun, you could walk down the street carrying it with no training whatsoever. To me, there is a lot more danger now with people thinking, 'I have the right to carry it so I'm going to carry it, and not have the training,'" Banaszynski said. Guns are still prohibited in schools and any private property owner, including businesses, can ban firearms from their property."