How is Child Support Calculated in Connecticut?

Connecticut combines both parents' net weekly incomes — not gross, and not monthly — into one figure, looks up the result on a state guidelines schedule under C.G.S. §46b-215a, and splits the obligation between the parents based on each one's share of that combined income. That's two things that set Connecticut apart from most income shares states: the calculation starts from income after taxes, not before, and it's measured weekly rather than monthly. A major guideline overhaul took effect August 1, 2026 — just under two weeks before this article was published — more than doubling the top of the income schedule and adding a new worksheet for families with three legal parents.

Connecticut's income shares model runs on net weekly income

Most income shares states — Kentucky and Louisiana among them — build their guidelines around each parent's gross monthly income. Connecticut does it differently. Courts start with each parent's net weekly income, meaning income after certain mandatory deductions come out, and they measure it weekly rather than monthly. Both parents' net weekly incomes are added together, and the combined total is matched against a schedule that sets a basic support obligation based on that total and the number of children.

The idea behind income shares is the same as in other states: a child should generally receive close to the same share of parental income they would have received if both parents lived in one household. Connecticut's net-and-weekly approach is simply a different way of measuring the inputs that go into that same basic idea.

How net weekly income is calculated

To get from gross income to net income, Connecticut's guidelines subtract federal and state income taxes, Social Security and Medicare withholding, and mandatory retirement contributions from each parent's gross weekly earnings. What's left is the net figure used in the calculation.

Income type	Generally included?
Wages, salaries, commissions, bonuses	Yes, before the standard deductions above
Self-employment income	Yes — gross receipts minus ordinary and necessary business expenses
Pension, retirement, and Social Security income	Yes
Paid Family and Medical Leave (PFML) benefits	Yes, as of the August 2026 guideline update
Alimony received	Yes
Means-tested public assistance (TANF, SSI)	Generally excluded

The August 2026 guideline overhaul: what changed

Connecticut's Commission for Child Support Guidelines revises the schedule periodically, and the version effective August 1, 2026 is the biggest overhaul in years. The headline change: the income schedule now runs up to $6,000 a week in combined net income, up from a $4,000-a-week ceiling under the prior guidelines.

Beyond the expanded ceiling, the August 2026 update also modernized the state's arrearage guidelines (the rules for calculating and collecting past-due support), refreshed the criteria for imputing income, and — as covered below — introduced Connecticut's first formal worksheet for families with three legal parents.

The basic calculation: combine, look up, split

Step	What happens
1. Determine net weekly income	Each parent's gross weekly income, minus taxes, FICA, and mandatory retirement contributions
2. Combine incomes	Both parents' net weekly incomes are added together
3. Find each parent's share	Each parent's income is divided by the combined total to get a percentage contribution
4. Look up the basic obligation	The combined net weekly income and number of children are matched against the state guidelines schedule
5. Split the basic obligation	Each parent's percentage share (step 3) is applied to the basic obligation (step 4)
6. Apply any deviation criteria	Shared physical custody, extraordinary expenses, or other recognized factors may adjust the presumptive number

This sequence produces the standard obligation before health insurance and child care costs are added at the end.

Worked example — the basic calculation

What the schedule looks like at the edges

At the very bottom of the schedule, combined net weekly income starts at $50, with a basic obligation for one child of roughly $14 a week at that floor — Connecticut doesn't set a separate statutory minimum order below the schedule itself. At the new top of the schedule, $6,000 a week in combined net income, the table now produces a specific dollar figure directly, where the old guidelines would have required a judge to extrapolate.

Shared physical custody can change the math

When a parent has the child for roughly 35% or more of overnights in a year — about 128 nights or more — Connecticut's guidelines treat that as a recognized deviation criterion. The reasoning is straightforward: when both parents are covering a substantial share of day-to-day costs directly, a straight percentage-of-income transfer from one parent to the other can overstate what's actually needed.

Connecticut's new three-parent worksheet

Effective with the August 2026 overhaul, Connecticut became the first state to build an explicit worksheet into its child support guidelines for situations involving three legal parents — for example, cases arising from certain surrogacy arrangements, second-parent adoptions, or other legally recognized multi-parent family structures. Rather than forcing a three-parent situation into a two-parent formula, the new worksheet apportions the basic support obligation among all three parents based on each one's share of the group's combined income, the same underlying logic as the two-parent model extended a third way.

Health insurance, medical expenses, and child care add-ons

The basic obligation from the schedule covers everyday costs like housing, food, and clothing. On top of that, reasonable uninsured medical expenses beyond routine care are generally divided between the parents in proportion to their income share. Whichever parent pays the premium for the children's health insurance typically receives credit for that portion of the premium. Work-related child care costs are usually added to the total obligation and split the same way, based on each parent's percentage of the combined net income.

For a broader look at how property division and alimony work alongside child support in Connecticut, see the Connecticut divorce finances overview. We also have a companion guide on how alimony is calculated in Connecticut, where courts weigh 12 statutory factors rather than applying a formula.

When can Connecticut child support be modified?

Either parent can ask the court to modify an existing order when there has been a substantial change in circumstances — a significant increase or decrease in either parent's income, a new parenting schedule, or a meaningful change in a child's medical or child care costs. Because the August 2026 overhaul changed the income schedule and ceiling so significantly, some families with existing orders may now have grounds to seek a modification based on the guideline change itself. Existing orders don't change automatically just because the guidelines did — a parent has to go back to court and ask. For more on how the general modification process works, see our guide on child support modification.

Common questions about Connecticut child support

How is child support calculated in Connecticut? Connecticut combines both parents' net weekly incomes, looks up the combined figure on the state guidelines schedule under C.G.S. §46b-215a, splits the resulting obligation based on each parent's income share, then adds health insurance and child care costs divided the same way. For a broader explanation of income shares versus other state models, see our general guide on how child support is calculated.

What changed in the August 2026 guidelines? The income schedule expanded from a $4,000-a-week combined net income ceiling to $6,000 a week, a new three-parent worksheet was introduced, income imputation criteria were updated, arrearage rules were modernized, and PFML benefits were added as countable income.

Does shared custody lower child support in Connecticut? It can. A parent with roughly 35% or more of overnights (about 128 nights a year) may qualify for a deviation that reduces the presumptive obligation, with the court required to make written findings explaining the departure.

Can Connecticut child support be modified? Yes, when there's been a substantial change in circumstances, including possibly the guideline overhaul itself for some families. Orders don't update automatically — a parent has to request the change through the court.