Adultery does affect divorce in New Hampshire, but far less dramatically than most people expect. It is recognized grounds for a fault-based divorce under RSA 458:7, and it can influence how a judge divides property or sets alimony. The catch is that fault only counts when it caused the marriage to break down and produced substantial suffering or economic loss. An affair that hurt feelings but didn’t drain accounts, wreck a career, or endanger a child rarely changes the numbers. More than 90 percent of New Hampshire divorces are granted on no-fault grounds, which tells you how often the fault route actually pays off.
When Adultery Actually Changes the Financial Outcome
New Hampshire divides marital property under equitable distribution. The court starts from a presumption that an equal split is equitable and then adjusts based on statutory factors. Fault is on that list, but with a specific gate: the court can consider it only when the fault caused the breakdown of the marriage and either caused substantial physical or mental pain and suffering, or resulted in substantial economic loss to the marital estate or the injured spouse.1New Hampshire General Court. New Hampshire Code 458:16-a – Property Settlement Both conditions have to be met.
The most common way adultery moves a property division is dissipation of marital assets. If a spouse drained joint accounts to fund the affair, paying for gifts, travel, a second apartment, or other expenses that benefited only the affair, the court can compensate the other spouse by awarding a larger share of what remains. What matters is a documented dollar figure that left the marital estate because of the affair. Without that financial trail, adultery alone is unlikely to shift the split in any meaningful way. New Hampshire courts focus on economic realities, not moral punishment.
Alimony works the same way, because the alimony statute cross-references the property division fault standard. RSA 458:19 tells the judge to weigh “the fault of either party as defined in RSA 458:16-a, II(l)” alongside length of the marriage, each spouse’s income and health, and standard of living.2New Hampshire General Court. New Hampshire Code 458:19 – Alimony So the same economic-harm gate applies: fault only counts toward support when it both caused the breakdown and led to real suffering or loss.
In practice, that plays out in a few ways. If the faithful spouse left a job or lost career momentum because of the emotional fallout, or if the unfaithful spouse spent down joint resources, those facts can justify a larger or longer award. If the cheating spouse is the one asking for alimony, the judge may look harder at whether their own conduct created the hardship they now claim. But an affair without financial impact rarely moves the needle.
What It Does to Child Custody
Custody in New Hampshire is decided under the best interests of the child standard in RSA 461-A:6. The statute lists factors like each parent’s relationship with the child, ability to provide a safe environment, developmental needs, and history of abuse. Adultery is not on the list.3Justia. New Hampshire Code 461-A:6 – Determination of Parental Rights and Responsibilities, Best Interest
There is a catch-all letting courts weigh “any other additional factors the court deems relevant,” and that is where an affair can enter the picture.3Justia. New Hampshire Code 461-A:6 – Determination of Parental Rights and Responsibilities, Best Interest What the court cares about is impact on the child. A parent who is frequently absent because of the affair, who prioritizes a new relationship over caregiving, or who exposes the child to a new partner who poses a safety concern gives the court a reason to weigh the conduct. The affair by itself is not the problem.
One important overlap: even in a no-fault divorce, evidence of misconduct is admissible when parental rights are at issue and the evidence is relevant to whether a proposed custody arrangement would harm the child.4New Hampshire General Court. New Hampshire Code 458:7-a – Absolute Divorce, Irreconcilable Differences Filing no-fault does not keep an affair out of the courtroom if custody is contested.
Fault or No-Fault: Which Path Makes Sense
New Hampshire offers two routes. RSA 458:7 grants a fault-based divorce “in favor of the innocent party” for specific reasons, adultery included.5New Hampshire General Court. New Hampshire Code 458:7 – Absolute Divorce, Generally RSA 458:7-a lets either spouse file no-fault based on irreconcilable differences.4New Hampshire General Court. New Hampshire Code 458:7-a – Absolute Divorce, Irreconcilable Differences
No-fault is faster, cheaper, and less adversarial. In a no-fault proceeding, the court generally will not hear evidence of specific misconduct unless parental rights are at issue or the judge decides such evidence is necessary to show the marriage has irretrievably broken down.4New Hampshire General Court. New Hampshire Code 458:7-a – Absolute Divorce, Irreconcilable Differences
Filing on fault grounds means you have to prove the adultery. That takes time, money, and evidence, and it tends to escalate hostility in ways that make negotiating custody and finances harder. The main reason to go that direction is when the affair caused documented financial damage to the marital estate or you need the court to weigh the conduct in dividing assets and setting alimony. If nothing financial was lost and custody is not in dispute, no-fault usually makes more practical sense. A fault-based case will almost always cost significantly more in attorney fees than a no-fault case because of the evidence gathering, additional hearings, and contested proceedings involved.
What Counts as Adultery in New Hampshire
The definition changed significantly in 2021. In the Matter of Blaisdell held unanimously that adultery under RSA 458:7 includes “voluntary sexual intercourse between a married person and someone other than that person’s spouse, regardless of the sex or gender of either person.”6Justia. In the Matter of Blaisdell – 2021 The court also read “sexual intercourse” to include genital contact beyond traditional penetration. Any intimate extramarital relationship now qualifies, regardless of the genders involved.
One boundary worth knowing: adultery is no longer a crime in New Hampshire. The state repealed its criminal adultery statute effective January 1, 2015.7New Hampshire General Court. New Hampshire Code 645:3 – Adultery It can end a marriage on fault grounds and shape financial outcomes, but nobody faces criminal charges for it.
Proving It Without Breaking the Law
The accusing spouse carries the full burden of proof. Most cases rely on circumstantial evidence rather than direct proof. Hotel receipts, credit card statements with unexplained charges, text messages, emails, and testimony from witnesses who observed the couple together can all support a claim. The evidence needs to show both an affectionate relationship with someone else and the opportunity to act on it. Weak or exaggerated claims backfire: if the evidence amounts to speculation, the court will not grant a fault-based divorce, and the accusing spouse can lose credibility on the rest of the case.
How you gather that evidence matters, because New Hampshire has some of the strictest electronic privacy laws in the country. Under RSA 570-A:2, intercepting a phone call, recording a conversation, or using a device to capture communications without the consent of every party is a class B felony.8New Hampshire General Court. New Hampshire RSA 570-A:2 – Interception and Disclosure of Telecommunication or Oral Communications Prohibited This is an all-party consent state. Federal law adds more layers. The Computer Fraud and Abuse Act prohibits accessing a spouse’s computer or phone without authorization, and the Stored Communications Act covers unauthorized access to email accounts and private messages held by service providers.
Illegally gathered evidence gets thrown out and can trigger criminal charges against the person who collected it. Logging into a spouse’s email without permission, installing spyware or GPS trackers, or breaking into private social media messages all create legal exposure. Screenshotting a public post is fine; breaking into a private account is not. The safest approach is to gather evidence from your own devices and accounts, save anything your spouse voluntarily shared with you, and let a licensed investigator handle surveillance.
Defenses That Can Sink an Adultery Claim
Recrimination
RSA 458:7 grants a fault-based divorce only “in favor of the innocent party.” The New Hampshire Supreme Court has held that a spouse who committed their own offense amounting to grounds for divorce cannot obtain a fault-based decree. If both spouses committed adultery, neither is the innocent party and neither gets a fault-based divorce. Timing matters: In re Ross established that adultery committed even after the divorce petition is filed can trigger this defense, because the statute requires innocence at the time of the decree, not just at the time of filing.9Supreme Court of New Hampshire. In the Matter of Danielle Ross and Christopher Ross
When recrimination blocks fault, the parties can still divorce on no-fault grounds. But if the case proceeds under the no-fault statute, fault generally cannot be considered in property division or alimony decisions.9Supreme Court of New Hampshire. In the Matter of Danielle Ross and Christopher Ross A spouse who starts an affair during the divorce can inadvertently destroy their own ability to use the other spouse’s adultery as leverage.
Condonation
Condonation means forgiving the adultery and continuing the marriage with knowledge of what happened. If the accused spouse can show that the other spouse knew about the affair, forgave it, and resumed the marital relationship, the claim may be barred. New Hampshire courts recognize the defense, but proving it takes specific evidence of reconciliation over a meaningful period, not just one conversation.