South Dakota recognizes adultery as one of six fault-based grounds for divorce under SDCL § 25-4-2. Proving infidelity can significantly impact alimony awards, with courts authorized to reduce or deny spousal support to the cheating spouse entirely. However, adultery has limited effect on property division unless the unfaithful spouse dissipated marital assets on the affair. The filing fee for divorce in South Dakota is $97 as of March 2026, and the state imposes a mandatory 60-day waiting period before finalization.
Key Facts: Adultery Divorce in South Dakota
| Factor | Details |
|---|---|
| Filing Fee | $97 (As of March 2026. Verify with your local clerk.) |
| Waiting Period | 60 days mandatory (SDCL § 25-4-34) |
| Residency Requirement | Must be resident at time of filing; no minimum duration |
| Adultery Grounds | Yes, fault-based ground under SDCL § 25-4-2 |
| Property Division | Equitable distribution; all-property state |
| Adultery Impact on Alimony | Significant; may reduce or eliminate spousal support |
| Adultery Impact on Property | Limited; only if dissipation of marital assets occurred |
| Adultery Impact on Custody | Minimal; only if relevant to parental fitness |
Is Adultery a Ground for Divorce in South Dakota?
South Dakota explicitly recognizes adultery as a fault-based ground for divorce under SDCL § 25-4-2, allowing the innocent spouse to cite infidelity as the legal reason for ending the marriage. The statute defines adultery under SDCL § 25-4-3 as voluntary sexual intercourse between a married person and someone of the opposite sex to whom they are not married. South Dakota is one of the minority of states that still permits fault-based divorce grounds alongside no-fault options.
The seven statutory grounds for divorce in South Dakota under SDCL § 25-4-2 include:
- Adultery
- Extreme cruelty
- Willful desertion
- Willful neglect
- Habitual intemperance (substance abuse)
- Conviction of felony
- Irreconcilable differences (no-fault)
Most divorces in South Dakota proceed under the no-fault ground of irreconcilable differences. However, fault-based grounds like adultery become strategically important in two scenarios. First, when your spouse actively contests irreconcilable differences and refuses consent, proving adultery may be necessary to obtain a divorce without agreement. Second, some spouses pursue adultery grounds to influence alimony awards, since South Dakota courts consider marital fault when determining spousal support.
How Does Adultery Affect Alimony in South Dakota?
Adultery can substantially reduce or completely eliminate a cheating spouse's alimony award in South Dakota, as courts weigh marital fault alongside financial factors when determining spousal support under SDCL § 25-4-41. A spouse whose misconduct caused the divorce may receive reduced alimony or no alimony at all, while the innocent spouse may receive a higher support award. South Dakota has no fixed statutory formula for calculating alimony, giving judges broad discretion to consider fault.
South Dakota divorce law recognizes three types of alimony:
- General alimony: Ensures the receiving spouse can maintain housing and provide for necessities
- Rehabilitative alimony: Helps the receiving spouse return to school or learn skills to become self-supporting
- Restitutional alimony: Reimburses a spouse for contributions made toward the other spouse's education or training during the marriage
The impact of adultery on alimony varies depending on case circumstances. Judges cannot use alimony purely to punish a guilty spouse. Courts can award alimony only when the innocent spouse needs support or to reimburse the innocent spouse for extraordinary amounts of marital funds the cheating spouse used to pay for an affair. If the unfaithful spouse spent $50,000 on hotel rooms, gifts, and trips with a paramour, the court may factor this dissipation into the alimony determination.
To successfully argue that adultery should affect alimony, you must provide concrete evidence that the affair occurred. South Dakota courts require proof beyond mere accusations. Evidence may include text messages, emails, photographs, credit card statements, witness testimony, or private investigator reports documenting the extramarital relationship.
Does Cheating Affect Property Division in South Dakota?
Adultery alone does not directly affect property division in South Dakota, but dissipation of marital assets on an affair can result in the cheating spouse receiving a smaller share of the marital estate. Under SDCL § 25-4-45.1, fault is generally not considered in property division except where relevant to the financial circumstances of the case. South Dakota follows equitable distribution principles and is an all-property state under SDCL § 25-4-44, meaning courts can divide all property belonging to either or both spouses.
The key distinction is between adultery as moral misconduct versus adultery involving financial misconduct. Simply proving your spouse had an affair will not typically change property division outcomes. However, if your spouse dissipated marital funds on the extramarital relationship, courts may award a larger share of remaining assets to the innocent spouse.
Examples of dissipation that may affect property division:
- Purchasing a vehicle, jewelry, or expensive gifts for a paramour
- Paying for hotel rooms, vacations, or trips with the affair partner
- Renting an apartment for the paramour using marital funds
- Transferring marital money to the affair partner
- Excessive spending on dates, dinners, and entertainment during the affair
South Dakota case law establishes seven principal factors courts consider when dividing marital property, based on the Guindon v. Guindon decision (256 N.W.2d 894). These factors include the contribution of each party to property accumulation (including non-monetary contributions like homemaking and child-rearing), the duration of the marriage, the age and health of each spouse, and economic misconduct such as dissipation of marital assets.
Does Adultery Affect Child Custody in South Dakota?
Adultery has minimal direct impact on child custody determinations in South Dakota, as courts focus primarily on the best interests of the child rather than marital misconduct. Under SDCL § 25-4-45.1, fault is generally not considered in child custody decisions except as it may be relevant to a parent's fitness. A parent's extramarital affair, standing alone, does not make them an unfit parent in the eyes of South Dakota courts.
However, judges may consider adultery indirectly when it affects parenting ability or exposes children to harmful circumstances. South Dakota courts might factor in infidelity if:
- The affair partner poses a danger to the children
- The cheating parent neglected child-rearing duties while conducting the affair
- The children were exposed to inappropriate situations related to the affair
- The affair demonstrates poor judgment affecting parenting decisions
- The parent prioritized the relationship over the children's needs
South Dakota law presumes that a child's best interest is to be in the care, custody, and control of their parents. Custody decisions under SDCL Chapter 25-5 focus on factors like each parent's ability to provide for the child's physical, emotional, and developmental needs; the child's adjustment to home, school, and community; and the mental and physical health of all individuals involved.
Contested vs. Uncontested Adultery Divorce in South Dakota
| Factor | Uncontested Divorce | Contested Adultery Divorce |
|---|---|---|
| Timeline | 60-90 days | 6-18 months |
| Total Cost | $2,000-$5,000 | $10,000-$25,000+ |
| Evidence Required | None (irreconcilable differences) | Proof of adultery required |
| Attorney Fees | $1,500-$3,500 | $5,000-$20,000+ |
| Filing Fee | $97 | $97 |
| Service Costs | $50-$75 | $50-$75 |
| Court Appearances | 1-2 hearings | Multiple hearings/trial |
Most divorce attorneys in South Dakota recommend filing under irreconcilable differences (no-fault) unless you have a strategic reason to prove adultery. Fault-based divorces require substantial evidence, extend the timeline, and increase costs significantly. The primary reasons to pursue adultery grounds include influencing alimony awards, forcing a divorce when your spouse refuses to consent, or documenting dissipation for property division purposes.
South Dakota law requires you to prove the adultery allegations. You cannot simply accuse your spouse of cheating without concrete evidence. Courts require clear and convincing proof that sexual intercourse occurred between your spouse and another person. Circumstantial evidence demonstrating opportunity and inclination may suffice, but direct evidence strengthens your case considerably.
South Dakota Divorce Filing Requirements
South Dakota has one of the most lenient residency requirements in the nation for filing divorce. Under SDCL § 25-4-30, the plaintiff must be a resident of South Dakota at the time the action is commenced. There is no minimum duration requirement. You can establish residency and file for divorce on the same day, provided you intend to remain in the state in good faith. Active-duty military members stationed in South Dakota also qualify to file.
Key filing requirements include:
- Residency: Must be a South Dakota resident at filing (no minimum duration)
- Filing location: Circuit Court in the county where either spouse resides
- Filing fee: $97 (includes $50 base fee, $40 automation surcharge, $7 law library fee)
- Service of process: Defendant must be served via sheriff or private process server ($50-$75)
- Waiting period: 60 days mandatory from date of service
The 60-day waiting period under SDCL § 25-4-34 cannot be waived or shortened under any circumstances. This cooling-off period applies to all divorce types, including uncontested, contested, and default divorces. The clock begins when the defendant is served, not when you file. During this period, the court may enter temporary orders regarding custody, support, and use of the marital residence.
South Dakota does not require a period of separation before filing for divorce. Spouses may continue living together throughout the proceedings until the judge issues the final decree.
Proving Adultery in South Dakota Divorce Court
Proving adultery in South Dakota requires evidence demonstrating that your spouse engaged in sexual intercourse with another person during the marriage. Courts accept both direct and circumstantial evidence, though direct proof strengthens your case significantly. The burden of proof falls on the spouse alleging adultery.
Acceptable evidence of adultery includes:
- Text messages, emails, and social media communications with the affair partner
- Photographs or videos documenting the relationship
- Credit card and bank statements showing expenditures on the affair
- Hotel receipts, airline tickets, and restaurant charges
- Testimony from witnesses who observed the affair
- Private investigator reports and surveillance evidence
- GPS tracking data showing suspicious locations and patterns
- Phone records indicating frequent contact with the affair partner
Circumstantial evidence establishing opportunity and inclination can prove adultery even without direct evidence of sexual intercourse. For example, evidence that your spouse spent the night at the affair partner's residence, combined with romantic communications, may satisfy the court's evidentiary requirements. Courts examine the totality of circumstances when determining whether adultery occurred.
Hiring a private investigator may help document the affair, though this adds $2,000-$5,000 or more to your divorce costs. An attorney experienced in fault-based divorce can advise whether the evidence you have is sufficient or whether additional investigation is warranted.
Defenses to Adultery in South Dakota Divorce
The spouse accused of adultery may raise several defenses to mitigate or eliminate the impact on divorce proceedings. South Dakota courts recognize traditional defenses including recrimination, connivance, condonation, and collusion, though these are rarely successful in modern practice.
Recrimination occurs when both spouses committed adultery. If both parties engaged in extramarital affairs, neither can claim the moral high ground. Courts may treat the parties equally and proceed as if no fault existed.
Connivance involves the innocent spouse actually facilitating or encouraging the adultery. If you arranged for your spouse to have an affair to obtain grounds for divorce, courts may reject your adultery claim.
Condonation means the innocent spouse forgave the adultery and resumed marital relations after learning of the affair. Continued cohabitation and sexual intimacy after discovering the infidelity may constitute condonation. However, isolated incidents of reconciliation attempts may not bar adultery claims.
Collusion occurs when both spouses fabricate adultery allegations to expedite the divorce. Courts will reject adultery grounds if the parties conspired to manufacture evidence.
Timeline for Adultery Divorce in South Dakota
An uncontested adultery divorce in South Dakota can be finalized in approximately 60-90 days, limited by the mandatory 60-day waiting period. Contested adultery divorces typically take 6-18 months depending on the complexity of discovery, motions, and trial scheduling.
Typical timeline milestones:
- Day 1: File divorce complaint citing adultery grounds; pay $97 filing fee
- Days 2-14: Serve defendant via sheriff or process server ($50-$75)
- Days 15-45: Discovery period; gather and exchange evidence of adultery
- Day 60: Earliest possible hearing date after waiting period expires
- Days 60-90: Final hearing and decree entry (uncontested cases)
- Days 60-540: Trial preparation and proceedings (contested cases)
Factors that extend the timeline include discovery disputes over evidence, motions to compel production of communications, depositions of witnesses, and court scheduling delays. Complex property division or custody disputes add additional time regardless of the adultery grounds.