Final answer:
A person's marital status for tax purposes is determined on December 31st of the tax year. This status affects the ability to file joint tax returns and access to other federal benefits, with marital status influencing both tax brackets and marginal tax rates.
Step-by-step explanation:
For tax purposes, a person's marital status is determined on the last day of the tax year, which is December 31st. If you are married on that day, you are considered married for the entire year for tax filing purposes, and if you are unmarried, divorced, or legally separated according to the laws of your state, you are considered unmarried for the whole year.
The ability to file a joint tax return and access various federal benefits, such as Social Security survivor benefits, can be affected by changes in marital status. In recent years, the recognition of same-sex marriages has evolved significantly, with the Supreme Court case United States v. Windsor playing a pivotal role in asserting that the definition of marriage is a state's prerogative.
Marital status can influence the tax bracket in which you fall and the marginal tax rates you face, which for a single taxpayer can range from 10% to 35% depending on income. The tax brackets are considered progressive, meaning that higher income ranges are taxed at higher rates. It's important to note that these rates and the ability to file jointly as a married couple do not just reflect a financial advantage but also represent a societal recognition of marital status.