Alimony, spousal support, spousal maintenance, or domestic partner support (collectively, spousal support) is generally financial support in the form of periodic payments (usually monthly) paid by one spouse or domestic partner to the other spouse or domestic partner (referred to as spouses) upon divorce. Financial support paid by one spouse to the other spouse while the divorce is pending is often called temporary support.

The law regarding eligibility for spousal support—including the number of years payments must be made and the amount of the payments—often depends on factors such as the length of the marriage, the spouses’ relative earning capacities, the dependent spouse’s education and employment skills, the time a dependent spouse needs to obtain sufficient education or training, and whether there was family violence in the marriage.

Spousal support payments are generally taxable income to the person receiving the payments and deductible for the person making the payments. Such payments generally terminate upon (1) the end of the court-ordered award or payment period; (2) the death of either spouse; or (3) the remarriage of the spouse receiving the payments. And in some states the court may terminate the payments if the spouse receiving payments cohabits (lives) with another person with whom they have a romantic relationship.

Spousal support laws vary from state to state and are generally located in a state’s statutes—often in the family or domestic relations code.

In Washington State, alimony, also known as spousal maintenance, is financial support that one spouse may be required to pay to the other during or after a divorce. The state's laws consider several factors when determining eligibility for spousal maintenance, including but not limited to the length of the marriage, the financial resources and earning capacity of each spouse, the standard of living established during the marriage, the age and physical and emotional condition of the spouse seeking maintenance, and the time necessary for the person seeking maintenance to acquire sufficient education or training to enable that person to find employment. Washington courts do not have a set formula for calculating the amount or duration of spousal maintenance; instead, these are determined on a case-by-case basis. Spousal maintenance payments are typically terminated upon the death of either spouse, the remarriage of the recipient spouse, or if the court finds that significant changes in circumstances warrant modification or termination of the support. It's important to note that as of the Tax Cuts and Jobs Act of 2017, for federal tax purposes, spousal support payments are no longer deductible for the payer and are not considered taxable income for the recipient for divorce or separation agreements executed after December 31, 2018.