On Thursday March 24, 2016, Idaho Governor Butch Otter signed Constitutional Carry into law in Idaho. Idaho had previously only required a permit within city limits, and this bill eliminates that requirement. The bill had been passed by veto proof margins in both the state House (54-15) and Senate (27-8). There are now 10 states that don't require a permit to carry anywhere in their states and Montana, which has the old Idaho regulation requiring permits within city limits. People can carry without a permit in Montana in 99.4% of the state. Mississippi is different than the other states in that you can carry without a permit as long as the gun is not carried in a pocket or a concealed holster -- people can carry in purses or fanny packs or some other carrying case.
In March this year, West Virginia also adopted Constitutional Carry. You can now carry concealed without a permit in: Alaska, Arizona, Arkansas, Idaho, Kansas, Maine, Montana (99.4% of state), Mississippi, Vermont, West Virginia, and Wyoming. Interestingly, these laws have frequently with very large legislative majorities in most states.