In Montana, a legal separation is a court decree that can settle parenting, support, and property while leaving you legally married. A divorce, which the statutes call a dissolution of marriage, settles the same things and ends the marriage. This page compares the two and explains how a separation converts to a dissolution. It is part of our Montana Divorce Guide.
What a Legal Separation Is
People use "separated" to mean living apart. In the Montana Code, a legal separation is something more specific: a decree entered by a district court in a case filed under Title 40, chapter 4. Moving out, or agreeing between yourselves to live apart, does not create one.
The statute is short. "If a party requests a decree of legal separation rather than a decree of dissolution of marriage, the court shall grant the decree in that form unless the other party objects" (MCA § 40-4-104(2)). Two things follow. A legal separation is an alternative form of decree in the same kind of case, and it depends on the other spouse not objecting.
How the Process Compares
The path to a legal separation looks like the path to a dissolution, because the same sections govern both:
- The verified petition "in a proceeding for dissolution of marriage or legal separation" must allege that the marriage is irretrievably broken and include the same information, including the jurisdictional requirements and a proposed parenting plan if there are children (MCA § 40-4-105(1)).
- The automatic economic restraining order is issued on the filing of a petition for legal separation, just as for a dissolution (MCA § 40-4-126(1)).
- Each spouse must serve financial disclosures in a legal separation case (MCA § 40-4-252(1)).
- Temporary maintenance, temporary child support, and other temporary orders are available (MCA § 40-4-121(1)).
- A written separation agreement can resolve the terms, and spouses who agree on everything may ask for a decree without a hearing (MCA §§ 40-4-201, 40-4-108(4)).
A legal separation is not a shortcut. It requires the same disclosures and the same decisions. See how divorce works in Montana for that sequence.
Legal Separation and Dissolution Side by Side
| Question | Legal separation | Dissolution |
|---|---|---|
| Are you still married afterward? | Yes | No |
| Can you remarry? | No. A marriage entered into before an earlier marriage is dissolved is prohibited (§ 40-1-401(1)(a)). | Yes, once the decree is entered (§ 40-4-108(1)). |
| Residency and breakdown findings | Same petition requirements (§ 40-4-105(1)) | § 40-4-104(1) |
| Parenting plan and child support | Yes (§§ 40-4-234(1), 40-4-204(1)) | Yes |
| Maintenance | Available on the same test (§ 40-4-203(1)) | Available (§ 40-4-203(1)) |
| Property division | The court "may" apportion property (§ 40-4-202(1)) | The court "shall" apportion property (§ 40-4-202(1)) |
| Can the other spouse block it? | Yes, by objecting (§ 40-4-104(2)) | No |
The property row is worth a note. In a dissolution the court "shall" equitably apportion the spouses' property, and "in a proceeding for legal separation may" do so (MCA § 40-4-202(1)). The same subsection lists "property acquired by a spouse after a decree of legal separation" alongside premarital, gifted, and inherited property, for which the court considers the other spouse's contributions if the property is later divided. See separate vs. marital property.
Converting a Legal Separation to a Divorce
A legal separation does not have to be permanent. "No earlier than 6 months after entry of a decree of legal separation, the court on motion of either party shall convert the decree to a decree of dissolution of marriage" (MCA § 40-4-108(2)).
Three points about that sentence:
- Either spouse can ask. It does not take both.
- The court "shall" convert. The statute does not give the other spouse a veto at this stage.
- Six months is a minimum, not a deadline. The statute sets no outer limit, so a decree of legal separation can stay in place as long as neither spouse moves to convert it.
The statute does not spell out which terms of the separation decree carry into the dissolution decree. That depends on how the separation decree and any agreement were written, so it is a point to settle with a lawyer when the separation is drafted, not at conversion.
Why People Choose a Legal Separation
The reasons are personal, and none of them is required by the statute. Reasons people give include religious or moral objections to divorce, uncertainty about whether the marriage is over, and a hope of keeping benefits that depend on being married. A legal separation gives enforceable orders about children and money in the meantime.
If the goal is time to reconcile, know that a pending dissolution can also be dismissed if spouses reconcile. See reconciliation and dismissing a divorce.
Health Insurance and Benefits Are Plan Questions
Some people consider legal separation to keep a spouse on employer health insurance. Montana's dissolution statutes do not decide that. The plan's own terms do, and plans differ on whether a legally separated spouse remains eligible.
Federal law shows why you cannot assume coverage continues. For employer plans covered by COBRA, the list of qualifying events includes "the divorce or legal separation of the covered employee from the employee's spouse" (29 U.S.C. § 1163(3)). A qualifying event is one that would otherwise cause a loss of coverage, so the statute itself contemplates that a legal separation can end eligibility under a plan.
The same caution applies to Social Security, pensions, military benefits, and tax filing status. Each has its own federal or plan rules about what counts as being married. Before choosing a legal separation for a benefit, confirm the rule with the plan administrator or the agency, and talk with a tax professional about filing status. Our pages on health insurance after divorce and Social Security and divorce cover the divorce side.
Which One Fits
If both of you want the marriage to end, a dissolution does that in one step. If one of you wants to stay married in name and the other does not object, a legal separation is available, with the understanding that either of you can convert it after 6 months. If you are not sure, a lawyer can explain what each decree would mean for your property, your children, and your benefits. See our Missoula divorce page or contact us.
This page explains Montana law in general as of the 2025 Montana Code Annotated. It is not legal advice about your specific situation.