The FDA classified electronic cigarettes as drug delivery devices and subject to regulation under the Food, Drug, and Cosmetic Act (FDCA) before importation and sale in the United States. However, many states and cities have adopted their own e-cigarette regulations as there is no specific federal regulations in place.

Canada:

Personal use of ecigs is allowed, you should not experience any trouble taking it through customs. Canada is very against electronic cigarettes but does not appear to have the legal basis to ban their use. Nevertheless, ecigarettes sent to Canada via mail are often seized.

North America:

  • Alabama: some localities ban vaping indoors
  • Alaska: some localities ban vaping indoors
  • Arizona: some localities ban vaping indoors
  • Arkansas: e-cigarette use banned on school property
  • California: no statewide vaping ban. Instead, vaping is only prohibited at Orange County Fair, including amphitheater, grandstand, and bleacher seating areas. Some localities ban vaping indoors
  • Colorado: vaping is legal however not permitted on school property.
  • Connecticut: vaping is banned.
  • Delaware: vaping is banned.
  • Florida: some localities ban vaping indoors
  • Georgia: ecigarette use banned in some localities.
  • Hawaii: vaping is banned.
  • Idaho: ecigs not allowed in some localities.
  • Illinois: some localities ban vaping indoors.
  • Indiana: some localities ban vaping indoors
  • Iowa: ecigs not allowed in some localities.
  • Kansas: ecigarette use banned in some localities.
  • Kentucky: some localities ban vaping indoors
  • Luisiana: some localities ban vaping indoors
  • Maine: vaping is banned.
  • Maryland: ecigarette use banned in some localities.
  • Massachusetts: some localities ban vaping indoors.
  • Michigan: ecigs not allowed in some localities.
  • Minnesota: some localities ban vaping indoors
  • Mississippi: ecigarette use banned in some localities
  • Missouri: some localities ban vaping indoors
  • Montana: ecigs banned in some localities.
  • New Hampshire: vaping is banned in public educational facilities and grounds.
  • New Jersey: vaping is banned
  • New Mexico: some localities ban vaping indoors.
  • New York: ecigs banned in some localities.
  • North Carolina: localities may regulate vaping indoors, but not in bars and restaurants.
  • North Dakota: vaping is banned.
  • Ohio: ecigs banned in some localities.
  • Oklahoma: vaping is legal.
  • Oregon: vaping is banned.
  • Pennsylvania: some localities choose to ban vaping.
  • South Carolina: ecigs banned in some localities.
  • South Dakota: vaping is allowed.
  • Texas: some localities choose to ban vaping.
  • Utah: vaping is banned.
  • Vermont: vaping is prohibited on school grounds and at child care facilities, both indoors and outdoors.
  • Virginia: vaping is prohibited on Virginia Railway Express trains and limited to 100 feet on north end of station platforms.
  • Washington: there is a ban on the use of electronic cigarettes in public places in King County, where Seattle Washington is located.
  • West Virginia: vaping banned in some localities.
  • Wisconsin: some localities choose to ban vaping.
Central America:
  • Caribbean: Unclear. 
  • Costa Rica: Regulated as tobacco product. 
  • Jamaica: There is no ban on electronic cigarettes, so you should be able to take them with you when you travel. However, the Ministry advises all products containing nicotine that are being imported for sale, require a registration and a permit.
  • Mexico: Banned import and sale. However, many vapers have reported no issues in regards to taking e-cigs though customs for personal use. 
  • Panama: Unclear.

South America: 

  • Argentina: vaping is banned.
  • Bolivia: unclear.
  • Brazil: vaping is banned.
  • Chile: unclear.
  • Colombia: unclear.
  • Ecuador: vaping is legal but treated as tobacco product.
  • El Salvador: vaping is legal. You can even get a card from the medical community to explain you are using at as a smoking cessation aid, and that it is harmless to those around you! (Thanks to Miguel for the update.)
  • French Guiana: unclear.
  • Guatamela: vaping is legal.
  • Guyana: unclear.
  • Paraguay: unclear.
  • Peru: unclear.
  • Suriname: vaping is banned.
  • Urugay: unclear.
  • Venezuela: unclear.