How late you can get an annulment depends on why the marriage qualifies for one. If the marriage is “void” under your state’s law, such as a bigamous or incestuous union, most states let you challenge it at any time because it was never legally valid. If it’s “voidable” for reasons like fraud, duress, mental incapacity, or being underage, you generally have between one and four years to file, and the clock usually starts when you discovered the problem rather than on the wedding day. Continuing to live as spouses after you learn the truth can shut the window even sooner.
Void vs. Voidable Marriages
Every annulment timing question starts with this split, because the category controls whether there’s a deadline at all.
A void marriage was never legally valid under any circumstances. The two most common examples are bigamy, where one spouse was already married to someone else, and incest, where the spouses are closely related by blood. Because a void marriage has no legal standing from day one, most states impose no deadline for challenging it. You could discover 20 years in that your spouse never divorced their first partner and still seek an annulment.
A voidable marriage is treated as legally valid until a court says otherwise. Grounds that make a marriage voidable include fraud, duress, mental incapacity, inability to consummate the marriage, and being underage at the ceremony. These marriages come with filing deadlines. Once those deadlines pass, the marriage becomes permanent regardless of the underlying problem, and the specific time limits vary by state and by the ground you’re claiming.
Deadlines by Ground
For voidable marriages, the deadline is tied to the specific defect, and the starting point for the clock varies too.
Fraud
Fraud is the most frequently cited ground, and it requires more than ordinary dishonesty. The deception has to go to something essential to the marriage itself: hiding an inability to have children, concealing a serious criminal history, or lying about an infectious disease. Lying about income or job title generally won’t qualify. The filing window typically runs one to four years, measured from the date you discovered the fraud, not the wedding date. Some states give you as little as one year once you learn the truth; others allow up to four.
Duress
If you were coerced into marrying through threats or physical force, most states start the clock from the date the coercion ended, not the ceremony. Someone still under threat can’t reasonably be expected to file court papers. The window after the duress ends is usually short, often one to two years, though it varies by jurisdiction.
Underage Marriage
When a person married below the legal age of consent without required parental or court approval, the deadline is usually tied to when the underage spouse turns 18. In many states, either the minor or a parent can file while the spouse is still underage, but the right to annul expires within a set period after the minor reaches adulthood. If the now-adult spouse continues living in the marriage past 18, courts in most states treat that as acceptance.
Mental Incapacity
Mental incapacity covers both permanent conditions like severe cognitive disabilities and temporary ones like being heavily intoxicated during the ceremony. The filing window generally runs from the date the person regains capacity or, for a permanent condition, from when a legal guardian discovers the marriage. Deadlines vary, but the principle is the same: once the incapacitated person or their guardian knows about the marriage and does nothing, the window starts closing.
How Staying in the Marriage Can End Your Right to File
Even if you’re within the statutory deadline, your own conduct can permanently block an annulment. This is called ratification, and it’s one of the most common reasons annulment petitions fail.
Ratification happens when you discover a valid ground for annulment and then continue living with your spouse as a married couple. A court will read that as accepting the marriage despite the defect. If you find out your spouse committed fraud during the engagement but stay in the relationship for another year, a judge will almost certainly rule that you ratified the marriage. The specific trigger is continuing to cohabit as spouses after learning the truth.
The ratification window is particularly narrow for underage marriages. If the couple keeps living together after the younger spouse turns 18, most courts treat that continued cohabitation as ratification and close the door.
One important exception: void marriages cannot be ratified. Because bigamous and incestuous marriages were never legally valid in the first place, no amount of continued cohabitation makes them valid, and you keep the right to seek annulment no matter how long you stayed.
What Counts as “Discovery” for Starting the Clock
Because most voidable-marriage deadlines run from discovery rather than the wedding, when you “knew” matters as much as when you file. For fraud, the clock starts when you learned of the deception. For duress, it starts when the coercion ended. For mental incapacity, it starts when the affected spouse regained capacity, or when a guardian learned of the marriage. For an underage spouse, the relevant date is the 18th birthday. Any evidence about when you found out — text messages, medical records, police reports, dated documents — becomes central to whether you filed in time.
Proving the Ground in Time Isn’t Enough on Its Own
Annulment is harder to obtain than most people expect. The law generally favors the validity of a marriage, so the person filing carries the entire burden of proving the marriage was defective from the start. Ambiguity in the evidence usually gets resolved in favor of keeping the marriage intact.
Courts require more than your testimony. For a fraud-based annulment, you’ll need documentary evidence, witness statements, or proof of your spouse’s contradictory behavior. For mental incapacity, medical records from around the time of the ceremony carry significant weight. For duress, evidence like police reports, protective orders, or witness accounts of threats helps establish the coercion. If your annulment petition fails because the evidence falls short, the court won’t grant you a divorce as a consolation prize. Your petition gets dismissed, and you start over. Many attorneys handle this by filing for both annulment and divorce in the alternative, which lets the court consider the annulment first and, if denied, proceed to a divorce without a new case.
If the Deadline Has Already Passed
If the ground you’d claim is voidable and the statutory window has closed, or if you stayed in the relationship long enough that a court would find ratification, annulment is off the table. Divorce is the path forward. Every state offers no-fault divorce, so you don’t need to prove wrongdoing to end the marriage. A family law attorney can tell you whether your facts still fit an annulment ground within the deadline in your state, and that consultation is worth the cost before you file anything: a failed annulment petition means starting the process over from scratch.