There are several areas right within the Greater Phoenix area that really aren't part of any incorporated city or town. In Maricopa County, where most of Greater Phoenix is located, there are people who might receive their mail at an address that says "Scottsdale" or "Gilbert" because those post offices service those areas, but they really don't live in those cities. They live in county islands.
What Is a County Island?
A county island is an area of unincorporated land which is completely surrounded by a city or town. County islands are created when a city or town annexes land into their corporate boundaries but excludes certain areas. Those excluded areas that remain under county jurisdiction are referred to as "county islands."
People who live in county islands usually don't receive services from the city that surrounds them. They might have to pay separately for water, sewer, and trash collection. In Maricopa County, the Maricopa County Sheriff's Office provides police protection to all unincorporated areas, including county islands. Maricopa County does not provide fire protection.
Arizona law prevents the creation of any new county islands. Property owners within existing county islands usually initiate an annexation by the city that surrounds the county island. While annexation of large areas of undeveloped land is a relatively simple task for cities and towns, it is more complex when an annexation involves multiple property owners. And it's even more complicated when the annexation involves land already developed.
Why Wouldn’t the Property Owners of a County Island Want to Be Annexed?
Many county island property owners would pay higher real estate taxes if they were annexed into a town or city.
Why Would the Property Owners of a County Island Want to Be Annexed?
Higher municipal taxes may be offset by an overall reduction in the total costs to the property owner for obtaining urban services. Examples are subscription to a private trash collection service, subscription to an emergency fire protection service or creation of a special taxing district for fire protection. People who reside in county islands may not vote in city elections of the city that surrounds them.
Why Wouldn’t a City or Town Want to Annex a County Island?
A city or town might be reluctant to annex certain county islands due to increased infrastructure and service delivery costs.
Where Are the County Islands in Maricopa County?
There are actually many small county islands within Maricopa County. Some of these areas are large enough to have their own names like New River, Rio Verde, Sun City, Sun City West, Sun Lakes, and Tonopah. Many other county islands are scattered across Maricopa County, predominantly in the northwest and southeast parts of the county.
A Common Misconception About County Islands
Sun City residents might not pay taxes to any local school districts, but that does not hold true for other county islands. Most of the county islands are located within a school district. If you live in a county island that is part of a school district, your children may attend those schools just like the children residing in the surrounding city.
County Island Trivia
The Phoenix Country Club in downtown Phoenix is a county island.
Thanks to the Maricopa County Planning & Development Department for providing the information about county islands for this article. County island details are subject to change without notice.