Florida Child Support Calculator: Income, Overnights, and Deviations

The Florida child support calculator runs on the formula in Section 61.30 of the Florida Statutes. It takes each parent’s monthly net income, looks up a base support amount on the statutory guidelines chart based on combined income and number of children, splits that amount between the parents by their share of income, then layers in health insurance, childcare, and an adjustment for how many overnights the child spends with each parent. The number the formula produces is presumed correct, though a judge can move it up or down in defined circumstances.¹

Start With Each Parent’s Net Income

Every calculation begins with monthly net income for each parent, and gross income is defined broadly. Wages, salary, bonuses, commissions, overtime, and tips all count. So do self-employment earnings (gross receipts minus ordinary and necessary business expenses), disability benefits, workers’ compensation, Social Security, pensions, retirement payments, dividends, interest, rental income after ordinary expenses, royalties, trust distributions, and spousal support received. Reimbursed expenses and in-kind payments count too, to the extent they reduce a parent’s living costs.¹

One item catches people off guard. If a parent receives Social Security disability or retirement benefits and the child receives a derivative benefit on that parent’s record, the derivative benefit gets added to that parent’s gross income for support purposes.¹

Deductions That Are Allowed

Only seven deductions convert gross income to net income under the statute:

Federal, state, and local income taxes, adjusted for the parent’s actual filing status and dependents
FICA or self-employment tax
Mandatory union dues
Mandatory retirement contributions (not voluntary 401(k) additions)
Health insurance premiums covering the parent personally, not the child’s coverage
Court-ordered support actually paid for other children under a prior order
Spousal support paid under a court order from a prior or current marriage

Nothing else reduces net income. Car payments, credit card debt, and voluntary retirement contributions do not lower the number the calculator uses.¹

Self-employed parents cannot simply import every write-off from their tax return. The statute allows only “ordinary and necessary expenses required to produce the income,” and a court can disallow deductions it considers inflated, personal, or aimed at suppressing income. Depreciation is a frequent point of dispute because it reduces taxable income without reflecting an actual cash outlay.¹

Find the Basic Obligation on the Guidelines Chart

Add the two parents’ monthly net incomes together. That combined figure gets matched against the guidelines schedule inside Section 61.30, a table that lists a dollar amount for each combined income level and number of children. The amount you find there is the basic obligation, the monthly total both parents together are expected to contribute toward the child.

Each parent’s share of that basic obligation matches their share of the combined income. A parent who earns 65% of the combined net income is responsible for 65% of the basic obligation.¹

Add Health Insurance and Childcare

Two categories get added on top of the basic obligation before the final number is set.

The premium for the child’s health insurance is a separate line item, covering only the portion attributable to the child (the parent’s own coverage was already deducted from gross income). Medical, dental, vision, and prescription costs not covered by insurance are added as well.²

Childcare costs necessary for a parent to work, look for work, or attend school are added too. The full obligation, once these costs are included, gets split between the parents using the same income-based percentages. If one parent already pays the insurance premium directly, the other parent’s share of that cost is built into the support payment so nothing is double-charged.¹

Adjust for Overnights

When both parents spend meaningful time with the child, the calculation changes to reflect that each home covers day-to-day expenses during its own time. The trigger is 20% of overnights per year, which is 73 nights. Once either parent crosses that threshold, the court applies what practitioners call the gross-up method.¹

The five steps:

Calculate each parent’s share of the basic obligation (without childcare and health insurance) and multiply each share by 1.5.
Determine the percentage of overnights the child spends with each parent.
Multiply each parent’s grossed-up obligation by the percentage of overnights the child spends with the other parent.
The difference between those two amounts is the base transfer payment from one parent to the other.
Add each parent’s proportional share of childcare and health insurance, crediting amounts already paid directly.

The 1.5 multiplier reflects that two households maintaining space for a child cost more than one. The overnight percentages ensure that the parent with fewer overnights pays a larger share of the grossed-up total, since the other parent is absorbing more direct daily costs.¹

Fewer than 73 overnights, and this adjustment does not apply. The standard income-shares calculation runs without the gross-up.

When a Judge Can Deviate From the Number

The output is presumed correct, not fixed. A judge can move support up or down by 5% without written explanation, as long as the adjustment considers the child’s needs and the parents’ finances. Anything beyond 5% requires a written finding that the guideline amount would be unjust or inappropriate.¹

Grounds the statute lists for deviation include:

Extraordinary medical, psychological, educational, or dental expenses
The child’s own income, excluding Supplemental Security Income
Seasonal or fluctuating earnings
The child’s age, since older children typically cost more
Special needs the family has historically absorbed
The impact of child-related tax credits and the dependency exemption
The 55% cap: if the formula would require a parent to pay more than 55% of gross income in current support from a single order, that alone is grounds for deviation
Meaningful time-sharing below the 20% threshold, which reduces the other parent’s expenses without triggering the gross-up
Significant travel costs for exercising time-sharing when parents live far apart

Courts also keep catch-all authority to make any adjustment needed for an equitable result, including reasonable debts the parties took on during the marriage.¹

When Income Gets Imputed

Quitting a job or moving to lower-paid work will not lower the calculator’s input. Florida courts can impute income, assigning an earning capacity, to any parent whose unemployment or underemployment is found to be voluntary. The court looks at recent work history, occupational qualifications, and prevailing wages in the community to set the imputed amount.¹

If a parent refuses to participate or fails to produce financial records, the court presumes that parent earns the median income of full-time, year-round workers as reported by the U.S. Census Bureau. The presumption can be rebutted, but the non-participating parent carries the burden.¹

There are limits. A court cannot impute income based on earnings records more than five years old, and generally cannot assume a parent can earn more than they ever have unless that parent recently obtained a new degree or professional license. A court may decline to impute income if it finds the parent needs to stay home with the child who is the subject of the case. Incarceration is not treated as voluntary unemployment, so a jailed parent’s obligation should reflect actual income and available assets during the period of incarceration.¹

How Long Support Runs

Support generally continues until the child turns 18. If the child is still in high school at 18, performing in good faith with a reasonable expectation of graduating, support continues until graduation or the 19th birthday, whichever comes first. Florida does not require parents to pay child support for college expenses.¹

1
Online Sunshine. Florida Statutes 61.30 – Child Support Guidelines; Retroactive Child Support
2
Florida Department of Revenue. Florida Child Support Program – Medical Support