In Hawaii, concealed carry of a firearm is legal for adults age 21 and older who are allowed by state and federal law to possess a firearm and who have a Hawaii license to carry. Concealed carry is allowed in private vehicles for license holders. Local jurisdictions may have stricter rules.
Leaving an unsecured firearm in an unattended vehicle is prohibited; firearms must be kept in a locked container and out of plain view. Carrying a loaded firearm without a license to carry, either openly or concealed and including in a vehicle, is a class B felony.
Permits
Permits are issued by the Chief of Police at the county level. Hawaii has very limited reciprocity; the state does not issue non-resident licenses and does not recognize handgun licenses from any other state.
Magazine capacity limits
Hawaii law limits magazine capacity to no more than 10 rounds.
Other weapons
No weapons other than handguns may be carried concealed.
Permitted non-lethal weapons include:
Duty to inform
Hawaii law requires drivers to notify police of the presence of a concealed weapon during traffic stops or at weigh stations.
Employee parking lots
This issue is not explicitly addressed in Hawaii state law.