How Child Support Is Calculated in Florida
Florida doesn’t leave child support to instinct. It’s a formula — and once you know the steps, you can see exactly where your number comes from.
Step 1: Combined Net Income
The calculation starts with the parents’ combined monthly net income — gross income from all sources, minus the specific deductions Florida law allows: taxes, mandatory union dues, mandatory retirement payments, health insurance premiums (other than for the children), and court-ordered support actually paid for others. This is the single most consequential input, and the single most common source of error — net, not gross.
Step 2: The Statutory Schedule
That combined net income is taken to the guideline schedule in section 61.30(6), Florida Statutes — the table printed on the courts’ Child Support Guidelines Worksheet (Form 12.902(e)). You find the row for the income and the column for the number of children, and it gives the basic obligation: the total monthly support need the law presumes for children at that income level.
Step 3: Split by Income Share — Not 50/50
Here’s what surprises people: the basic obligation is divided between the parents in proportion to their share of the combined income, not down the middle. A parent earning 65% of the household income carries 65% of the basic obligation, regardless of who the children live with.
Step 4: Additions and Credits
On top of the basic obligation, the formula adds child care costs incurred for work (or qualifying job search or education), the children’s health insurance cost, and uncovered medical, dental, and prescription costs — unless the court orders those paid separately on a percentage basis. Payments a parent has already actually made for those categories are credited against that parent’s share.
Substantial Time-Sharing: The 73-Overnight Adjustment
When each parent has at least 73 overnights a year — 20% of the year — the worksheet switches to what it calls the gross-up method: the basic obligation is increased by 50%, each parent’s share is multiplied by the other parent’s share of overnights, and the two amounts are netted. It exists because two households cost more than one. Note what this does not mean: equal time does not automatically mean no support. (Most free online calculators quietly get this part wrong — ours implements it.)
Above $10,000 a Month
The schedule stops at $10,000 of combined net monthly income. Above that, the formula continues by formula: the top schedule amount, plus a fixed percentage of everything over $10,000 — from 5% for one child up to 12.5% for six.
The 5% Line
The resulting guideline amount is presumptive. A court can order more or less — but a variation beyond 5% requires written findings, after considering factors like the needs of the children, their standard of living, and each parent’s financial status. That threshold is why the inputs matter so much: a modest change in income or overnights can move the number within the band courts accept without findings.
What This Means for Mediation
The formula is fixed. What mediation actually settles is what goes into it: each parent’s real income (contested when someone is self-employed), the real cost of child-related expenses, and the time-sharing schedule itself. Arrive at agreed inputs and the number follows. For more on where the room to move is, see whether child support is negotiable — and you can run the formula yourself with the estimator.
This article is general information about how the statutory formula works, not legal advice, and it does not calculate anyone’s child support. Individual results depend on facts and, where the parties don’t agree, on the court.