The 3949-A is a financial disclosure form the court uses to set or change child support amounts

Form 3949-A, officially called the Child Support Case Registry Form, is a document you file with the court when you are involved in a child support case. It collects your income, expenses, and financial details so the judge can calculate what child support should be. The form itself does not determine the amount — the judge does — but without accurate information on this form, the calculation will be wrong or incomplete.

You file this form when you first open a child support case, and again whenever you ask the court to change the amount you pay or receive. Both parents typically must file one. The court uses the numbers you report to apply state child support guidelines, which are formulas that account for both parents' income, custody time, and other costs like health insurance and childcare.

If you do not file the form or file it with false information, the court can set child support based on what it knows or assumes about your income — which is often higher than your actual earnings. You can also face penalties for lying on the form.

Key Takeaways

  • Form 3949-A requires you to report your gross income, deductions, expenses, and assets so the court can calculate child support using state guidelines.
  • Both parents must file the form in most cases, and you file it again whenever you request a change to the support amount.
  • The form is filed with the court, not sent directly to the other parent, though they receive a copy during the case.
  • Incomplete or false information on the form can result in a higher support order or legal penalties.
  • You should attach recent pay stubs, tax returns, and proof of expenses to support the numbers you report.

What information goes on the 3949-A form

The form asks for your gross monthly income from all sources: wages, self-employment, rental income, Social Security, unemployment, disability, bonuses, and commissions. You list the income before taxes or deductions are taken out. If your income varies month to month, you average it over the past year or report what you expect to earn going forward — the instructions on the form tell you which approach to use.

You then report your mandatory deductions: federal and state income tax, Social Security tax, Medicare tax, and court-ordered support you pay to other children or a former spouse. These reduce your income before child support is calculated. You do not deduct groceries, rent, or other living expenses — those are not part of the calculation.

The form also asks about childcare costs, health insurance premiums, and uninsured medical expenses for the child in this case. These are added back into the calculation because the law treats them as shared costs between parents. You report the total amount you pay and the portion that covers the child you are supporting.

Finally, you list your assets — savings, vehicles, property — and any other children living in your home. The judge uses this information to understand your overall financial picture, though assets do not directly change the support amount in most states.

When you file the form and what happens next

You file the 3949-A form when you first ask the court to open a child support case, either through the child support agency (usually called the Department of Child Support Services or similar) or by filing directly with the court. If the other parent also files one, you both submit your forms before the court hearing or conference.

The court or child support agency reviews both forms and calculates a presumed child support amount using state guidelines. This is the amount the law says should be paid based on the income and expenses you reported. The judge can order this amount, or can deviate from it if there are special circumstances — for example, if one parent has the child more than half the time, or if the income difference between parents is very large.

If you later want to change the support amount, you file a new 3949-A form showing your current income and expenses. The court will only modify the order if your circumstances have changed significantly — usually a 10 to 15 percent change in income, though this varies by state.

What documents to attach to your form

The 3949-A form requires you to attach proof of the income and expenses you report. For employment income, attach your most recent pay stubs (usually the last two or three months) and your last federal tax return. If you are self-employed, attach your tax return and profit-and-loss statement for the past year.

For childcare and health insurance costs, attach invoices, receipts, or statements showing what you actually pay. If you pay for childcare through an employer plan, attach the summary of benefits. For health insurance, attach the premium statement or a copy of your insurance card showing the monthly cost.

If you report other income — rental income, Social Security, unemployment — attach the documentation that shows the amount and frequency. Do not guess or estimate. The court will ask for proof, and if you cannot provide it, the judge may disregard that income or assume it is higher than you claimed.

What happens if you do not file or file incomplete information

If you do not file the 3949-A form by the deadline the court sets, the judge can hold a hearing without you and set child support based on whatever information is available. This often means a higher amount than you would have reported, because the court may estimate your income upward or use only the other parent's financial information.

If you file the form but leave out income or report false expenses, the other parent or the child support agency can challenge it. The judge can order you to provide proof, and if you cannot, the court will disregard your claim. Deliberately lying on the form is perjury and can result in criminal charges, though this is rare in routine child support cases.

If your circumstances change after the court orders child support — you lose your job, your income increases, or your childcare costs drop — you can file a new 3949-A form and ask the court to modify the order. You do not have to wait for a specific time period, but the change must be substantial enough that the judge thinks it is worth reopening the case.

How the form connects to child support guidelines in your state

Every state has a child support guideline formula that the judge must use to calculate the amount. The formula takes the combined income of both parents, subtracts mandatory deductions and childcare costs, and then divides the remaining amount between the parents based on how much time each parent has the child. The 3949-A form provides all the numbers that go into this formula.

Some states use an "income shares" model, which assumes both parents contribute to the child's expenses in proportion to their income. Others use a "percentage of income" model, where the paying parent gives a set percentage of their income. A few states use a hybrid. Regardless of the model, the 3949-A form is the document that feeds the numbers into the calculation.

If you believe the guideline amount is unfair — for example, because one parent has the child far more than half the time, or because the income difference is extreme — you can ask the judge to deviate from the guideline. But you still need to file the 3949-A form first, because the judge needs to see what the guideline amount would be before deciding whether to change it.

Frequently Asked Questions

Can I file the 3949-A form online or does it have to be on paper?

This depends on your state and county. Some courts accept electronic filing through their website or a court portal; others require paper copies mailed or delivered to the courthouse. Contact your local child support agency or the court clerk to find out what method your jurisdiction uses. If you file electronically, you usually still need to print and sign the form, then scan it to upload.

What if my income is irregular or I am self-employed?

Report your average income over the past 12 months, or your expected income for the next 12 months if it will be different. Attach your last two years of tax returns and your profit-and-loss statement. If you are between jobs or your income is very low, report what you actually earned or expect to earn — do not leave it blank. The judge can impute income (assume you earn more than you report) if they think you are underreporting on purpose.

Do I have to tell the other parent what I put on the 3949-A form?

No, you file it with the court. However, the other parent receives a copy as part of the case discovery process, usually before the hearing. You cannot hide information from them or the judge. If you want to discuss your finances with the other parent before filing, you can, but you are not required to.

What if the other parent does not file a 3949-A form?

The court can still proceed with your form alone, though the judge may estimate the other parent's income or hold a hearing to question them about it. If the other parent refuses to file or provide financial information, the judge can hold them in contempt of court. You can ask the court to compel them to file by a certain date.

Can I change the information on my 3949-A form after I file it?

You can file an amended form if you made a mistake or if your circumstances changed before the court hearing. After the judge orders child support, you file a new form only when you ask for a modification. Do not simply resubmit the form without telling the court — file it as part of a formal request to change the support amount.