Adultery in Montana: Does Cheating Affect Alimony?

If you're getting divorced in Montana and you or your spouse has cheated, you'll need to know how the adultery will affect the judge's decisions about your case, including alimony, child custody, and child support.

By , Attorney · Cooley Law School

Adultery can be devastating to a marriage. In some states, a spouse who commits adultery during the marriage isn't eligible to receive alimony. In these states, if you're responsible for breaking up the marriage by cheating, you lose the right to receive financial support from your spouse after the divorce.

If you're going through a divorce resulting from adultery, you might be wondering whether it will affect your or your spouse's right to alimony in Montana. This article explains some of the basics of alimony in Montana and how adultery might impact your award in a divorce.

Overview of Alimony in Montana

When couples divorce, often one spouse does not have enough income to make ends meet. For this reason, courts in Montana often order the spouse with more financial resources (the paying spouse) to make payments to the other spouse (the supported spouse). These payments are called alimony, or "spousal maintenance," in Montana.

For a Montana court to award alimony, the court must decide that a spouse doesn't have enough property or funds to pay for reasonable needs. The court also has to find that the spouse can't work or has childcare duties that would make it inappropriate to work. (Mont. Code Ann. § 40-4-203(1) (2021).)

Courts usually order a paying spouse to pay alimony in monthly amounts, called "periodic alimony." However, depending on the circumstances of your case, the judge may order you to pay in a lump sum or by transferring property. Alimony can be permanent, lasting until the supported spouse dies or remarries, or temporary, lasting a certain period of time, or until some event happens, such as the supporting spouse completing school or getting a job.

Courts consider the following factors when deciding whether to award alimony:

  • each spouse's financial resources, including marital property from the divorce
  • each spouse's ability to meet their financial needs independently
  • how long it would take for the spouse seeking alimony to find a job
  • the spouse's standard of living during the marriage
  • the duration of the marriage
  • the age and health of the spouse seeking alimony, and
  • the ability of the spouse paying alimony to support both spouses' needs.

(Mont. Code Ann. § 40-4-203(2) (2021).)

Montana doesn't use a formula to calculate alimony. Instead, the judge will consider the case's facts and circumstances and determine an appropriate amount and term for support.

How Does Adultery Impact Alimony in Montana?

Montana law states that spouses owe each other mutual respect and fidelity. Therefore, being unfaithful to your spouse is breaking the contract of marriage. However, cheating on a spouse doesn't make you ineligible to receive alimony in a divorce or separation in Montana. On the contrary, Montana law states explicitly that courts can't consider any marital misconduct when determining alimony. (Mont. Code Ann. § 40-4-203(2) (2021).)

What Else Does Adultery Impact?

Montana law is clear that adultery and other types of marital misconduct do not affect alimony. Adultery also usually does not affect the court's property division during a divorce or separation.

However, the court may consider any money spent on an affair during the marriage when deciding how to divide the couple's property. Still, it won't award a cheating spouse less property for the affair itself.

Adultery and Child Support and Custody

In a divorce, the court will resolve several divorce-related issues, such as property division, maintenance, child support, and child custody. Unlike property division and alimony, judges don't have much discretion when determining child support. Instead, judges must follow Montana law, which requires judges to consider the:

  • child's financial resources
  • parents' financial resources (each parent's income)
  • child's standard of living if the parents remained married
  • child's physical and emotional condition, educational, and medical needs
  • child's age
  • cost of daycare
  • final parenting plan, and
  • each parent's obligation to financially support another child or individual.

In addition to laying out the above factors, Montana law clarifies that judges may not consider either parent's marital misconduct when finalizing a child support award. Instead, the judge will enter both parent's information into the state's calculator and create an order. (Mont. Code Ann. § 40-4-204 (2021).)

Child Custody

Although judges have some leeway in deciding child custody, they must still follow Montana law and always consider what's in the child's best interest before making a final custody order. (Mont. Code Ann. § 40-4-212 (2021).) Judges will consider a parent's marital misconduct only when the parent continues the behavior and it negatively impacts the child's physical, mental, or emotional health. For example, suppose a parent had an affair with an individual with a violent criminal history and, after the divorce, the new partner abuses or threatens to abuse the child. In that case, the court could limit or deny custody or parenting time.


To read the full text of Montana's alimony law, see Montana Code Annotated section 40-4-203.