TAT License Advertising Rules Forthcoming January 4, 2016 Act 204, Session Laws of Hawaii 2015, became effective January 1, 2016, and requires that operators of transient accommodations designate an on-island local contact and display that contact's name, phone number and email address inside the unit, and provide that information either in online advertisements, or to the guest upon check-in. Act 204 also requires that a unit's TAT license number be displayed both inside the unit itself and in all online advertisements, either directly in the advertisement or by a link. Temporary administrative rules will be issued shortly to help clarify the TAT license number advertising and posting requirements, including how penalties may be assessed.

Visitor Aloha Society of Hawaii - Visitor Assistance Resource

Below is a small sampling of the Many articles and News Videos which have been written about the Illegal Vacation Rental problems facing Hawaii.
While these problems are Well Known, very little has been done to actually enforce the existing laws, as rationalized by a number of people and agencies.
It is loosely estimated that up to 25,000 Vacation Rentls / B and B's exist in Hawaii with as Little as 1,000 actually having Legal status and TAT Registration Numbers.
Huge amounts of GET and TAT Taxes are being Lost by the State of Hawaii, again with numerous ineffective explanations.
Tourism and Our Hawaii Guest Visitors are crucial to Hawaii's economy.
These funds are supposed to help maintain a Beautiful and Safe Hawaii for Locals and Visitors alike.
This is a Big Problem that has to be dealt with.
Meanwhile the onus is upon individual visitor guests to help protect themselves and to have a safe vacation in Hawaii.
All online advertisements Are REQUIRED to display their TAT (Transient Accommodation Tax Registration Number)
Don't be shy about asking any prospective host for their TAT Number.
Travel Safe.
B and B Coalition : Don't Risk Your Hawaii Vacation

Pacific Business News : The Hawaii vacation rental revolution

Maui news : Illegal vacation rentals tackled in Honolulu bills

Hawaii Vacation Rental Owners and Homeowners' Associations Face Increased Disclosure Requirements And Penalties Under New Law

Hawaii News Now Article: City to Crack Down on Illegal Vacation Rentals

Honolulu Civil Beat Article: Report Indicates Oahu's Illegal Vacation Rentals Outnumber Permitted Ones

TripAdvisor Blog Discussion : Hawaii Illegal Rental Units

Civil Beat : Honolulu Zoning Committee to Tackle Illegal Vacation Rentals

Who Is Responsible for Adhering to the Vacation Rental Laws in Hawaii?

Hawaii News Now : Kailua has most illegal vacation rental violations

Honolulu Magazine : The Bed and Breakfast Battle in Hawaii