Most parents walking into a child support case think the number is going to be negotiable. It usually isn’t, at least not in the way they’re imagining. New York uses a statutory formula called the Child Support Standards Act, and the result it produces is presumptively correct. Judges deviate from it, but the deviation has to be justified on the record. At Roven Law Group, clients often arrive with a number in their head based on what a friend pays or what they found on a calculator app, and the actual figure looks different once the real income numbers, add-ons, and statutory cap get plugged in.
Here’s how the math actually works in New York, and where the misconceptions tend to land.
The CSSA Formula in Plain Terms
The Child Support Standards Act, codified at DRL § 240(1-b) and FCA § 413, applies a percentage to combined parental income based on the number of children:
- 17% for one child
- 25% for two children
- 29% for three children
- 31% for four children
- No less than 35% for five or more children
These percentages apply to combined parental income up to the statutory cap, which is adjusted every two years for inflation. Effective March 1, 2026, the cap is $193,000, up from $183,000.
The calculation runs in four steps. Each parent’s gross income gets reduced by FICA taxes and New York City income tax (where applicable) to arrive at adjusted CSSA income. The two adjusted incomes are combined, multiplied by the applicable percentage, and then divided pro rata between the parents based on each one’s share of the total. The non-custodial parent pays their pro rata share to the custodial parent.
A working example helps. Parent A earns $120,000 after FICA. Parent B earns $60,000. Combined CSSA income is $180,000, all under the cap. For two children, the basic support obligation is 25% of $180,000, or $45,000 per year. Parent A’s share is 67%, which works out to roughly $30,000 per year, or $2,500 per month, payable to Parent B as the custodial parent.
What the Formula Doesn’t Cover
Basic child support is meant to handle food, clothing, and shelter. It does not include several categories that get treated as mandatory add-ons under the statute. These are split between the parents pro rata, on top of the basic obligation:
- Health insurance premiums for the child
- Unreimbursed medical, dental, and mental health expenses
- Work-related or education-related childcare costs
- Educational expenses where appropriate, including private school where the family circumstances support it
Extracurricular activities, summer camp, religious instruction, and tutoring sit in a discretionary category. Courts in Manhattan and the Bronx will often order these to be split pro rata as well, particularly when they reflect the standard of living the child enjoyed before the parents separated, but the analysis is more case-by-case than the mandatory add-ons.
Income Above the $193,000 Cap
This is where most of the strategy in a high-earning NYC case happens. For combined parental income above $193,000, the court has discretion under DRL § 240(1-b)(c)(3) to either apply the same CSSA percentages to the excess income or look at ten statutory factors to decide what additional support, if any, is appropriate.
The Court of Appeals in Matter of Cassano v. Cassano, 85 N.Y.2d 649 (1995), made clear that courts can extrapolate the percentages above the cap, and in practice, Manhattan judges often do extrapolate, particularly when the child’s pre-separation standard of living warrants it. A family that took international vacations and sent the children to private school does not suddenly become a family living at the $193,000 cap level just because the statute permits it.
The ten factors the court considers include the financial resources of both parents, the physical and emotional health of the child, the standard of living the child would have had if the household had stayed intact, tax consequences, non-monetary contributions, educational needs, and the relative disparity in the parents’ incomes. The factors are flexible, and that’s where experienced advocacy makes a measurable difference in the final number.
Common Misconceptions Roven Law Group Sees Most Often
A few patterns come up so often they’re worth flagging directly.
The first is the assumption that 50/50 parenting time eliminates child support. It doesn’t. New York is not a true shared-custody state for support purposes. Under Bast v. Rossoff, 91 N.Y.2d 723 (1998), the parent with the higher income is generally treated as the non-custodial parent for CSSA purposes even in a near-equal time split, and that parent pays support.
The second is the belief that a parent can simply quit a job or take a lower-paying position to reduce the obligation. Courts impute income based on earning capacity, work history, education, and the local job market. A surgeon who decides to become a yoga instructor will be ordered to pay based on what the surgeon could earn.
The third is the assumption that self-employment income is whatever shows up on the Schedule C. Forensic accountants spend significant time identifying perquisites, deductions, and pass-through distributions that get added back into income for CSSA purposes. Business owners going through a child support case need to expect that scrutiny.
The fourth is the belief that a private agreement to waive child support will hold up. It won’t. Child support belongs to the child. Parents can’t contract it away in a separation agreement or prenup, and a court can revisit the number any time circumstances warrant.
When Courts Deviate From the Formula
The presumptive CSSA amount can be set aside when applying it would be unjust or inappropriate. The statute lists ten deviation factors, and the court has to make written findings explaining the deviation. Common scenarios that lead to deviation:
- Extraordinary expenses for a child with special needs
- One parent’s income falling below the self-support reserve, currently $21,128
- Substantial visitation expenses, including travel costs for a parent in another state
- Educational expenses already being covered directly by the non-custodial parent
- Non-recurring income like a one-time bonus or inheritance distorting the calculation
A skilled deviation argument is built on documentation, not narrative. Bank statements, tuition invoices, medical records, and tax returns drive these motions more than sympathy does.
The Bottom Line
The CSSA gives child support in New York a clear starting point, but the work that shapes the actual order is in how income gets calculated, what add-ons are included, and whether the case justifies extrapolation above the $193,000 cap or a deviation below it. Janice G. Roven has been handling these calculations for NYC families for more than 35 years, including high-income matters and self-employment cases that require forensic accounting. To get a realistic read on what child support is going to look like in your situation, schedule a consultation with Roven Law Group.
