When a service member and a co-parent separate, there is often a gap of weeks or months before a court order or a signed agreement sets child support. Each military service has its own rule for that gap. These rules are separate from the state child support guidelines a court will later use, and they stop applying once a court order or a written agreement is in place. This guide explains what each service's rule says, how BAH-DIFF fits in, and where to read the rule for yourself.
Why the military has its own support rules
The military does not set child support in place of a court. The Navy's rule says this directly: the Department of the Navy does not have the authority to decide purely civil matters, and it wants support to be set by agreement between the parties or by a civil court. What the services do have is a standard of conduct. Until there is an order or an agreement, each service expects its members to provide a minimum level of support, and a commander can act when a member does not.
Once a court order or a written support agreement exists, that order or agreement controls. The Army's regulation, for example, makes it a violation for a Soldier not to follow the financial support terms of a court order or a written financial support agreement, and it applies its own interim rule only when neither exists.
Army: AR 608-99
Army Regulation 608-99, dated November 13, 2020, sets the Army's interim support rule in paragraph 2-6. When there is no court order or written agreement, a Soldier provides support based on BAH RC/T at the with-dependents rate for the Soldier's pay grade. BAH RC/T is a single, non-locality rate, so it does not depend on where the Soldier is stationed or on how much housing allowance the Soldier actually receives.
- One family living off post. The Soldier provides an amount equal to BAH RC/T with dependents to the family.
- Family members in different places. Each family member who does not live in government family housing receives a pro-rata share. A pro-rata share is the BAH RC/T with-dependents rate divided by the total number of supported family members.
- Family in government housing. The Soldier is not required to provide additional support while the family lives in government family housing, except for enhanced interim support for a spouse under paragraph 2-6f.
- Both parents on active duty. A Soldier does not owe interim support to a spouse who is also on active duty. If the Soldier has no custody of the children and the children do not live in government quarters, the Soldier provides BAH-DIFF to the military parent who has custody.
The regulation also says that, with limited exceptions, a Soldier's support obligation does not depend on whether the Soldier receives any form of BAH. Receiving or not receiving BAH generally does not change what the Soldier owes under the regulation.
Navy: MILPERSMAN 1754-030
The Navy's rule is in Military Personnel Manual article 1754-030. When no court order or agreement sets support, the article gives a scale based on a fraction of gross pay. For children with no spouse involved, the scale is one-sixth of gross pay for one minor child, one-fourth for two minor children, and one-third for three minor children. The scale has separate fractions when a spouse is also being supported.
For this scale, gross pay means basic pay plus any BAH or Overseas Housing Allowance the Sailor is entitled to. It does not include hazardous duty pay, sea or foreign duty pay, incentive pay, or BAS. The article calls the scale an interim guide and says it is not meant to be used as a basis for any court proceeding.
Air Force and Space Force: DAFI 36-2906
The Department of the Air Force, which includes the Space Force, covers family support in Department of the Air Force Instruction 36-2906, Personal Financial Responsibility. Its latest version is dated August 23, 2023, and incorporates Change 1 from March 31, 2025. The instruction tells commanders to advise members that they are expected to provide adequate financial support to their family members. When a family member complains of nonsupport, the commander is to require proof of adequate support.
When there is no support agreement or court order, the instruction requires a pro-rata share for each supported family member as an interim measure. The share is the non-locality BAH with-dependents rate for the member's grade divided by the total number of supported family members. A member is not required to make this payment to family members living in government family housing when that housing causes the member to forfeit BAH.
The instruction also ties support to housing allowance. If a member receives BAH at the with-dependents rate or the BAH-DIFF rate only because of the support they provide to a family member, that allowance is authorized only when the member's monthly support is at least the BAH-DIFF amount. If support falls below that, the Air Force can cancel the allowance and recoup past payments, regardless of what a court order or agreement says.
Marine Corps: MCO 5800.16, Volume 9
The Marine Corps covers dependent support in Volume 9 of the Legal Support and Administration Manual, MCO 5800.16, which addresses dependent support and paternity. Volume 9 applies once a family member makes a complaint of nonsupport to the Marine's commanding officer. When no court order or written agreement sets support, each family member entitled to support receives at least a pro-rata share of the BAH or OHA the Marine is entitled to. The share is one-half for one family member, one-third for two, one-fourth for three, one-fifth for four, one-sixth for five, one-seventh for six, and a smaller share for each additional family member. The total interim support is capped at one-third of the Marine's gross military pay. Ask your installation legal assistance office how these rules apply to you.
What BAH-DIFF is, and what it is not
The Department of Defense describes BAH-DIFF as the housing allowance for a member assigned to single-type quarters who is authorized a housing allowance only because they pay child support. A member is not entitled to BAH-DIFF if their monthly child support is less than the BAH-DIFF amount. BAH-DIFF rates are published each year.
The Army's regulation defines BAH-DIFF as the difference between the BAH RC/T with-dependents rate and the without-dependents rate for the Soldier's pay grade. In the Army, BAH-DIFF shows up in two different ways. It is an allowance some members receive, and it is also the amount a dual-military Soldier without custody provides to the other parent in the situation described above. These are separate questions, and getting the allowance is not the same as meeting a support obligation.
When a court or agency sets support
When a court or a state child support agency sets a new support order, it uses its own state's child support guideline. Under the Uniform Interstate Family Support Act, the court or agency hearing the case applies its own state's law and guidelines. Some terms of an existing order, such as how long it lasts, stay governed by the state that issued it. That is why our military calculator asks you to choose the state where your case is, or will be, heard, and then sends you to that state's calculator. Your duty station and your state of legal residence do not choose the guideline on their own.
If military duty keeps you from taking part in a court case, the Servicemembers Civil Relief Act lets an active duty member who applies with the required documents ask for a stay of a civil proceeding of at least 90 days.
Where to get help
- Installation legal assistance. Military legal assistance offices help eligible service members and family members with family law questions, subject to the availability of legal staff.
- Your chain of command. Your command can tell you how it applies your service's support rule.
- Your state child support agency. The agency in the state where the case is filed can open a case and set an order.
Disclaimer: This article is educational only and is not a substitute for legal advice. Military support rules change, so always read the current version of your service's regulation and talk to a legal assistance attorney or a family law attorney about your situation. Any calculator result on this site is an educational estimate only.
Sources
- Army Regulation 608-99, Family Support, Child Custody, and Parentage, 13 November 2020, paras 1-9 and 2-5 to 2-6: armypubs.army.mil
- MILPERSMAN 1754-030, Support of Family Members, para 4a; Navy Region Legal Service Office, Family Law: Custody and Paternity: jag.navy.mil
- DAFI 36-2906, Personal Financial Responsibility, 23 August 2023, incorporating Change 1, 31 March 2025, paras 3.2.1 to 3.2.6 and Chapter 4 (para 4.1): e-publishing.af.mil
- MCO 5800.16, Legal Support and Administration Manual, Volume 9, Dependent Support and Paternity, 01 May 2018, paras 010212, 010403 and 010406: marines.mil; MARADMIN 273/18: marines.mil
- Department of Defense, Types of BAH (BAH-Differential): militarypay.defense.gov
- Uniform Interstate Family Support Act §§ 303, 604 and 611, as summarized by the federal Office of Child Support Services: acf.gov
- Servicemembers Civil Relief Act, 50 U.S.C. § 3932; OCSS Military Trainer Guide, Module 4: acf.gov
- 10 U.S.C. § 1044, Legal assistance: law.cornell.edu