In addition to income taxes, most states collect revenue from other types of taxes that require their own forms. For example, your state may impose an estate tax similar to the federal estate tax. If so, the state can create its own rules that require you to file an estate tax return even if the federal government doesn’t require one.
Similarly, some states impose an inheritance tax on beneficiaries who receive money or property when a friend or family member passes away, and will require you to report your inheritance on specific forms. Although these are just two examples, there is an array of other state taxes that individuals, businesses and trusts must prepare state tax forms for each year.