How to File for Full Custody in Massachusetts: Forms and Filing Steps

To file for full custody in Massachusetts, you file a complaint in the Probate and Family Court for the county where your child lives, asking the judge for sole legal custody, sole physical custody, or both. “Full custody” is not a term the statute uses. You will need to specify which kind of sole authority you want, meet a few threshold requirements before filing, and be ready to show the court that the arrangement serves your child’s best interests.

What “Full Custody” Means in Massachusetts

Massachusetts divides custody into two categories, and a judge can award sole or shared versions of each one independently.

Sole legal custody gives one parent exclusive authority over major decisions about education, medical care, and religious upbringing.
Shared legal custody splits that decision-making authority between both parents.
Sole physical custody means the child lives primarily with one parent; the other may still have parenting time unless the court finds contact would harm the child.
Shared physical custody means the child splits time between both homes with enough contact to keep a meaningful relationship with each parent.

Judges mix and match. A common arrangement is shared legal custody paired with sole physical custody to one parent, so the child has a stable home while both parents weigh in on major decisions.¹ When you file, say plainly which type of sole custody you are asking for.

Before You File: Residency and Paternity

Two threshold requirements must be met before the Probate and Family Court will hear your case. Your child must have lived in Massachusetts for at least six consecutive months immediately before filing, and parentage must be legally established if the parents were never married.²

If you are married to the other parent, custody is handled inside your divorce case, and you raise your custody request in the Complaint for Divorce alongside property, support, and other marital issues.

If you were never married, the filing path depends on paternity. Under Massachusetts law, the person who gave birth has sole custody of a child born outside of marriage until paternity is adjudicated or voluntarily acknowledged, and the birth parent keeps custody even after paternity is established unless a court order says otherwise.³ An unmarried father seeking custody must first establish legal paternity, either by signing a Voluntary Acknowledgment of Parentage with the other parent or by filing a Complaint to Establish Paternity.

The Forms You Need to File

Three core documents open a custody case.

The Complaint

For unmarried parents, use the Complaint for Custody, Support, and Parenting Time (CJD 109), which is used exclusively for children born to unmarried parents. It asks for both parents’ legal names and addresses, the child’s name and date of birth, and the specific custody arrangement you want.⁴ For married parents, the custody request goes inside the Complaint for Divorce.

Child Care or Custody Disclosure Affidavit

This sworn form tells the court about any existing court orders or ongoing legal proceedings involving your child. It is required in every case involving the care or custody of a child.⁵

Financial Statement

Every party in a custody case must disclose their finances. The short form is for anyone earning less than $75,000 per year before taxes; the long form is for anyone earning more.⁶ You will list income, regular expenses, assets, and debts, so gather recent pay stubs, bank statements, and tax returns before you start.

Where to File and What It Costs

File your complaint at the Probate and Family Court in the county where your child lives. If your custody request is part of a divorce, the correct court may instead be in the county where you and your spouse last lived together.

The total filing cost for a custody complaint is $120: a $100 base filing fee, a $15 surcharge, and a $5 summons fee.⁷ Filing electronically adds a one-time $22 e-filing fee plus a credit card processing charge.⁸

If you cannot afford the fees, file an Affidavit of Indigency. Massachusetts law allows any party in a civil proceeding to ask the state to cover court costs based on financial need.⁹

Serving the Other Parent

After filing, you must formally deliver a copy of the complaint and the court-issued summons to the other parent. You cannot hand the papers over yourself. Massachusetts requires service by a sheriff, deputy sheriff, or special sheriff, though the court can appoint another person to handle delivery.¹⁰ The person who serves the papers then files a Return of Service with the court to prove the other parent was notified.

If you do not know where the other parent lives, you can ask the court for an order of notice allowing an alternative method like publication in a newspaper, but only after a sheriff or constable has made a documented attempt to find them.¹¹

What Happens After You File

Once served, the other parent has 20 days to file a written Answer responding to your complaint.¹² The court will then schedule an initial event, typically a case management conference, where both parties appear before a judge or court staff to identify the issues, set a schedule for exchanging financial information, and decide whether temporary orders are needed.

Temporary Orders

If you need a custody arrangement in place while the case is pending, file a Motion for Temporary Orders (Form CJD 400) with a supporting affidavit and a proposed order. The court schedules a hearing on the motion, and any temporary order stays in effect until it is replaced by another order or the final judgment.²

In divorce cases, temporary orders are where the presumption of shared legal custody bites hardest. If you want sole legal custody while the case is pending, come to that hearing prepared to explain specifically why shared decision-making would not work for your child.

Mandatory Co-Parenting Course

In contested cases, both parents must complete “Two Families Now,” a four-hour online co-parenting education course. Register within 30 calendar days of service, complete the course within 30 days of registering, and file the Certificate of Completion within 14 days after finishing. The fee is $49 per parent unless the court waives it, and missing a deadline can result in sanctions.¹³

Mediation

The court may refer both parents to mediation to resolve some or all custody issues without a trial. Mediation is not binding unless both parties reach an agreement the court approves. If it fails, the case continues through normal litigation.

How the Judge Decides

The court’s only concern is the child’s happiness and welfare. The relevant factors differ slightly depending on whether the parents are divorcing or were never married.

Divorce Cases

In a divorce, Massachusetts law starts from the position that both parents’ rights are equal, absent misconduct, and the court then looks at whether the child’s present or past living conditions have harmed the child physically, mentally, or emotionally.¹⁴

While the divorce is pending, the law creates a temporary presumption of shared legal custody. A judge can override that presumption and grant temporary sole legal custody, but only after making written findings that shared custody would not serve the child’s interests, considering factors like alcohol or drug abuse, abandonment, and whether the parents can cooperate on decisions.¹⁴ There is no equivalent presumption for shared physical custody; the judge has full discretion over where the child lives from the start.

Unmarried Parents

For unmarried parents, the court weighs a different set of factors: the child’s relationship with the primary caretaker, where and with whom the child has lived during the six months before the case was filed, and whether each parent has built a genuine parental relationship with the child. Joint custody for unmarried parents requires either a written agreement or evidence that the parents already shared parenting responsibilities successfully before the case began.³

When Abuse Is Part of Your Case

If you are seeking sole custody because the other parent has been abusive, Massachusetts law tilts in your favor. When a court finds by a preponderance of the evidence that a parent committed a pattern of abuse or a single serious incident of abuse, a rebuttable presumption applies: the abusive parent should not receive sole custody, shared legal custody, or shared physical custody.¹⁵

Abuse here means attempting to cause or causing bodily injury, or placing someone in reasonable fear of imminent bodily injury. A serious incident raises the bar to serious bodily injury or forcing someone into sexual relations through force or threats. The abusive parent can try to overcome the presumption, but the burden falls on them to show that custody in their hands still serves the child’s best interests. For unmarried parents, the statute similarly directs the court to treat evidence of past or present abuse as a factor working against the abusive parent’s claim.³

Guardian ad Litem Investigations

In contested custody cases, the judge may appoint a Guardian ad Litem (GAL) to investigate and report back. The GAL is not an advocate for either parent; the role is impartial fact-finder, gathering information to help the judge decide what arrangement serves the child.¹⁶

A GAL investigation typically involves interviewing both parents, observing the child with each parent, visiting both homes, and talking to teachers, doctors, or therapists who know the child. The GAL then submits a written report to the court and may include custody recommendations if the appointing order allows. Judges take these reports seriously, and a GAL recommendation that goes against you can be difficult to overcome at trial.

GAL costs vary with the complexity of the case and the hours required. The court decides how the cost is split between the parents, and in some cases one parent bears the entire expense. Budget for this possibility if your case is headed toward a contested hearing.

Changing the Order Later

A custody order is not permanent. Either parent can file a Complaint for Modification if circumstances change significantly after the original order. The court applies a two-part test: a material change in circumstances since the last order, and a showing that the requested change serves the child’s best interests. Meeting only one prong is not enough. Common triggers include a parent relocating, a substantial change in a parent’s living situation or work schedule, the child’s evolving needs, or evidence that the current arrangement is harming the child. The process mirrors the original filing, including service on the other parent and a court hearing.

1
Mass.gov. Learn About the Types of Child Custody Arrangements
2
Mass.gov. Get an Immediate Child Custody or Parenting Time Order
3
Mass.gov. Massachusetts General Laws Chapter 209C Section 10
4
Mass.gov. Probate and Family Court Complaint for Support, Custody, Parenting Time Pursuant to G.L. c. 209C (CJD 109)
5
Mass.gov. Miscellaneous Probate and Family Court Forms – Section: Child Care or Custody Disclosure Affidavit
6
Mass.gov. File the Short Financial Form
7
Mass.gov. Probate and Family Court Filing Fees
8
Mass.gov. Probate and Family Court eFiling: Custody, Support, Parenting Time
9
Mass.gov. Indigency (Waiver of Court Fees)
10
Mass.gov. Civil Procedure Rule 4 – Process
11
Mass.gov. Completing Service of Process If You Don’t Know Where the Defendant Lives
12
Mass.gov. Respond to a Case Filed Against You in Probate and Family Court
13
Mass.gov. Notice to Parents for Mandatory Co-Parenting Education Course
14
General Court of Massachusetts. Massachusetts General Laws Chapter 208 Section 31
15
General Court of Massachusetts. Massachusetts General Laws Chapter 208 Section 31A
16
Mass.gov. Standard 1 – The Role of the GAL Investigator