When Montana parents cannot agree on a parenting plan, the judge does not ask which parent is better. The judge asks what arrangement is in the best interest of the child, using the factors in MCA § 40-4-212. The same standard applies when a judge reviews a plan the parents propose. This page sets out every factor in plain words and is part of our Montana Divorce Guide.
What the Statute Tells the Court to Do
Subsection (1) has two key sentences. First: "The court shall determine the parenting plan in accordance with the best interest of the child." Second: the court "shall consider all relevant parenting factors, which may include but are not limited to" the list that follows.
Two things follow from that wording. The list is a starting point, so a court may consider something that matters to your child even if it is not named. And the statute does not rank the factors or assign them points. Which ones carry weight depends on the evidence.
The 13 Factors in MCA § 40-4-212(1)
| Subsection | Factor | In plain words |
|---|---|---|
| (a) | The wishes of the child's parent or parents | What each of you is asking for, and why. |
| (b) | The wishes of the child | The child's own view. It is one factor, not a vote. |
| (c) | Interaction and interrelationship with parents, siblings, and others who significantly affect the child | The relationships the child actually has. |
| (d) | Adjustment to home, school, and community | How settled the child is where the child lives now. |
| (e) | Mental and physical health of all individuals involved | The health of the child, the parents, and others in the picture. |
| (f) | Physical abuse or threat of physical abuse by one parent against the other parent or the child | Violence and threats inside the family. |
| (g) | Chemical dependency or chemical abuse on the part of either parent | Substance problems that bear on parenting. |
| (h) | Continuity and stability of care | Who has been providing care, and how steady it has been. |
| (i) | Developmental needs of the child | What a child of this age and stage needs. |
| (j) | Knowing failure to pay birth-related costs the parent is able to pay | The statute treats this as not in the child's best interests. |
| (k) | Knowing failure to financially support a child the parent is able to support | The statute treats this as not in the child's best interests. |
| (l) | Whether the child has frequent and continuing contact with both parents | Treated as in the child's best interests unless a court finds, after a hearing, that contact with a parent would be detrimental. |
| (m) | Adverse effects from continuous and vexatious parenting plan amendment actions | The harm repeated litigation does to a child. |
"Chemical dependency" in factor (g) is a defined term borrowed from another part of the code (MCA § 53-24-103). Factor (b), the child's wishes, has its own page: does my child get to choose.
Contact With Both Parents
Factor (l) is the closest the statute comes to a policy statement about parenting time. Frequent and continuing contact with both parents "is considered to be in the child's best interests unless the court determines, after a hearing, that contact with a parent would be detrimental to the child's best interests."
In making that determination the court must consider evidence of physical abuse or threat of physical abuse by one parent against the other parent or the child. That includes whether a parent, or another person living in that parent's household, has been convicted of one of the crimes listed in MCA § 40-4-219(8)(b), a list that includes deliberate homicide, sexual assault, endangering the welfare of children, partner or family member assault, and strangulation of a partner or family member.
Factor (l) speaks of contact. It does not mention equal time or any particular schedule. We look at that distinction in is 50/50 parenting the default.
Factors About Money and Litigation Conduct
Three factors are less about the child's daily life and more about how a parent has behaved. Factors (j) and (k) say that a parent who has knowingly failed to pay birth-related costs, or to financially support a child, when able to do so, has acted in a way that is considered not in the child's best interests. Both turn on the words "knowingly" and "able to." A parent who cannot pay is in a different position from one who chooses not to.
Factor (m) asks about adverse effects on the child from "continuous and vexatious parenting plan amendment actions." Returning to court again and again is itself something a judge may weigh.
Special Rules in the Rest of the Section
Subsections (2) through (4) add rules that sit alongside the factors:
- Military service. For the child of a parent in military service, the court considers all the factors and "may not determine the best interest of the child based only upon the parent's military service" (MCA § 40-4-212(2)). See military divorce in Montana.
- Informal arrangements. When parents have been following a de facto arrangement and there is no prior parenting decree, a parent does not have to prove the amendment factors in MCA § 40-4-219 (MCA § 40-4-212(3)). The court decides under the best interest factors.
- Filing soon after a support case. A parenting plan action brought by a parent within 6 months after a child support action against that parent is presumed vexatious (MCA § 40-4-212(4)(a)).
- Amending without complying first. A motion to amend a final plan is presumed vexatious if the parent has not made a good faith effort to comply with the plan or with its dispute resolution provisions (MCA § 40-4-212(4)(b)).
The two presumptions are rebuttable, and they apply "unless contrary to the best interest of the child." Why they matter is explained in amending a parenting plan.
How a Court Learns the Facts
Factors are only as useful as the evidence behind them. Parents testify and offer records. The court may also appoint a guardian ad litem, order an investigation and report, or interview the child in chambers. Those tools are covered in guardians ad litem and parenting evaluations.
If abuse is part of your situation, your safety comes first. If you are in danger, call 911. The National Domestic Violence Hotline is 1-800-799-7233.
Using the Factors When You Negotiate
The factors matter even if your case never reaches a trial. They are the measure a court uses when it reviews a proposed plan, and they are a practical checklist when you are deciding what to propose: what your child is used to, what your child needs at this age, and how each of you will support the child's relationship with the other. A&M Law works with parents in contested cases and through its Cooperative Family Law process.
This page explains Montana law in general as of the 2025 Montana Code Annotated. It is not legal advice about your specific case.