There is not only one answer to this question; the length of time an alimony/spousal support order will last depends on the judge’s discretion. The main factor a judge looks at when deciding how long a spousal support order will last is the length of the marriage.
If a couple is ending a long-term marriage (typically 10 years or longer), a judge may continue a spousal support order indefinitely. Conversely, if it is a marriage of short duration, (typically 8 years or less) support will be ordered for half the length of the marriage. Certain events may end an order early such as the recipient remarrying.