What Is an Annulment? How It Differs From Divorce

An annulment is a legal ruling that a marriage was never valid to begin with, treating it as though it never legally existed. This is the fundamental difference from divorce: a divorce ends a valid marriage, while an annulment declares that there was no valid marriage in the first place. Annulments are only available on specific legal grounds, things like fraud, bigamy, or one party being underage, and because those grounds are limited, annulments are far less common than divorces. In short, divorce dissolves a real marriage; annulment erases one that was legally defective from the start.

People often want an annulment because of its appealing premise, that the marriage simply never happened, but the reality is narrower than the appeal. Here's how annulment actually works, the grounds you need, the difference between void and voidable marriages, and how it compares to divorce in practice.

The core difference: ending versus erasing

The cleanest way to understand annulment is to contrast it directly with divorce, because the difference is conceptual, not just procedural.

A divorce takes a valid, legally recognized marriage and ends it. The marriage existed, it was real and legal, and the divorce terminates it going forward. After a divorce, you're a divorced person, formerly married. A divorce doesn't deny that the marriage happened; it just ends it.

An annulment, by contrast, declares that the marriage was never legally valid in the first place, due to some defect that existed at the time of the marriage. The legal effect is to treat the marriage as though it never existed. After an annulment, in the eyes of the law, you were never validly married at all. The marriage is voided, erased, rather than ended.

This distinction sounds abstract, but it flows from a concrete question: was there ever a valid marriage? If yes, you need a divorce to end it. If no, because something made it invalid from the start, an annulment recognizes that it was never valid. You can't annul a perfectly valid marriage just because you want it erased rather than ended; you need legal grounds showing the marriage was defective.

The grounds for annulment

Because annulment is about a marriage being invalid from the start, you can only get one if specific grounds existed at the time of the marriage. These vary somewhat by state, but the common grounds fall into recognizable categories.

Fraud or misrepresentation is one of the most common, where one spouse deceived the other about something fundamental to the marriage, lying about a critical matter that goes to the essence of the marital relationship. Not every lie qualifies; it generally has to be serious and central to the decision to marry.

Bigamy, where one spouse was already legally married to someone else at the time, makes the second marriage invalid, you can't validly marry someone who's already married.

Being underage, where one or both parties were below the legal age to marry and lacked the required consent, can make the marriage voidable.

Lack of capacity to consent, where one party couldn't truly consent to the marriage, due to mental incapacity, or being under the influence of drugs or alcohol to the point of not understanding what they were doing, can be grounds.

Duress or force, where someone was coerced or forced into the marriage against their will, undermines the consent a valid marriage requires.

Incest or other legal prohibitions, where the marriage was between people too closely related or otherwise legally barred from marrying, makes it invalid.

And inability or concealment regarding fundamental matters, like a concealed inability to consummate the marriage or a hidden fact central to the marriage, can be grounds in some states.

The common thread is that all these defects existed at the time of the marriage and go to its validity. An annulment isn't for problems that developed later, those call for divorce. It's for marriages that were flawed from the very beginning.

Void versus voidable marriages

A useful distinction within annulment is between void and voidable marriages, because they're treated differently.

A void marriage is one that was never legally valid and is considered invalid from the start, automatically, regardless of what the parties do. Bigamous marriages and incestuous marriages are typically void, they're against the law and never valid, period. A void marriage is invalid whether or not anyone seeks an annulment, though getting a formal annulment provides legal clarity.

A voidable marriage is one that's valid until a court declares it invalid. It has a defect that gives one party the right to seek an annulment, but it remains a valid marriage unless and until that party acts to annul it. Marriages involving fraud, duress, underage parties, or lack of capacity are typically voidable, the wronged party can choose to annul, or can choose to stay married, in which case the marriage remains valid. If they don't seek annulment, or if they continue the marriage after learning of the defect, they may lose the right to annul.

The practical upshot is that void marriages were never valid no matter what, while voidable marriages are valid until someone with grounds successfully gets them annulled. This affects who can seek the annulment and whether the right can be lost over time.

What happens to property, support, and children

A common question is whether annulment, by treating the marriage as never having existed, wipes out the financial and parental consequences a divorce would address. The answer is more nuanced than the "never existed" framing suggests.

Even when a marriage is annulled, courts can still address practical matters, particularly involving children and sometimes property. Children born during a marriage that's later annulled are still the legal children of both parents, annulment does not make them "illegitimate," and issues of custody and child support are decided based on the children's best interests just as in a divorce. The children's rights don't evaporate because the marriage was voided.

Property and support are handled differently across states. Some states have provisions for dividing property acquired during a putative marriage or awarding support in annulment cases, while others treat annulment as more cleanly erasing the marital financial relationship. Because annulment's premise is that there was no valid marriage, the marital-property and spousal-support framework that applies in divorce may not apply the same way, which is one reason the financial outcome of an annulment can differ from a divorce and why the specifics depend heavily on state law.

Legal annulment versus religious annulment

One frequent source of confusion: a legal annulment and a religious annulment are completely different things. A legal annulment is a court ruling that affects your legal marital status. A religious annulment, such as one granted by the Catholic Church, is a religious determination that affects your standing within that faith, like the ability to remarry in the church, but has no effect on your legal marital status.

You can have one without the other. A religious annulment does not legally end or void your marriage in the eyes of the state, and a legal annulment doesn't address your religious standing. People who want both have to pursue them separately, through the court for the legal one and through their religious institution for the religious one. Don't assume a religious annulment changes your legal status, or vice versa.

Why annulment is less common than people think

Many people are drawn to the idea of annulment over divorce, preferring the notion that the marriage never happened rather than carrying the status of "divorced." But annulment is genuinely uncommon compared to divorce, for a simple reason: most marriages that end were validly formed, and a valid marriage can't be annulled just because the couple wants out. Without specific grounds showing the marriage was defective from the start, the only route is divorce.

Annulments are also often associated with short marriages, since the grounds, fraud, lack of consent, and the like, tend to surface or be acted upon early, but the length of the marriage isn't itself what determines eligibility; the grounds are. A short marriage with no qualifying defect still requires a divorce, while a marriage void from the start (like a bigamous one) can be annulled regardless of how long it lasted. The Legal Information Institute maintains a plain overview of the grounds and how annulment works.

Frequently asked questions

What is the difference between annulment and divorce?

A divorce ends a valid marriage, the marriage was real and legal, and the divorce terminates it. An annulment declares that the marriage was never valid in the first place, treating it as though it never legally existed, because of a defect present at the time of the marriage. Divorce dissolves a marriage; annulment erases one. You can only get an annulment on specific legal grounds showing the marriage was invalid from the start, whereas divorce doesn't require proving the marriage was defective.

What are the grounds for an annulment?

Annulment requires specific grounds that existed when the marriage was formed, commonly fraud or misrepresentation about something fundamental, bigamy (one spouse already married), being underage, lack of capacity to consent (due to mental state or intoxication), duress or force, and incest or other legal prohibitions. The defect must go to the marriage's validity and have existed at the start. Problems that developed after a valid marriage call for divorce, not annulment.

Are children from an annulled marriage considered illegitimate?

No. Children born during a marriage that's later annulled remain the legal children of both parents. Annulment does not make children "illegitimate" or strip them of any rights. Custody and child support are decided based on the children's best interests, the same as in a divorce. The voiding of the marriage affects the spouses' marital status, not the parent-child relationships or the children's legal standing.

An annulment offers something divorce can't, a legal declaration that the marriage never validly existed, but only when specific grounds make it available. For most ending marriages, which were validly formed, divorce is the route, while annulment is reserved for the narrower set of marriages that were legally defective from the very beginning.