A tax haven is a state or foreign government, most often offshore, which allows an individual or corporation to "hide" money, in a technically legal fashion, from their nationality's tax system and therefore avoid paying taxes on that money.
Also certain states, such as those in the American Redoubt have no sales tax (Oregon and Montana), or no income tax (Alaska, Florida, Nevada, New Hampshire, South Dakota, Tennessee, Texas, Washington, and Wyoming – see Free State Wyoming) or very low property tax (Idaho) and are considered to be more "free states" for that reason and others such as Second Amendment gun rights concealed carry and open carry freedom
Before making a strategic relocation or "vote with your feet" move to another state or country, be sure to research the various tax rates and the relative cost of living. These websites might prove useful: