Question 1

What's the difference between Income Shares, Percentage of Obligor Income, and Melson?

Accepted Answer

Income Shares (38 states + DC): both parents' incomes combine into a 'combined adjusted gross income' figure; the state's guideline table assigns a basic obligation amount; the obligor (non-custodial parent) pays their proportional share. Most common — based on the policy theory that children should receive the proportion of parental income they would have received if the family remained intact. Percentage of Obligor Income (6 states): only the obligor's income matters; the obligation is a flat percentage that scales by number of children. Simplest math, fewest disputes, but doesn't account for the custodial parent's income. Melson (3 states): a hybrid that starts with Income Shares logic but reserves a 'self-support reserve' for the obligor and then adds a Standard of Living Allowance (SOLA) for additional discretionary support. Most complex; most progressive.

Question 2

Which model does my state use?

Accepted Answer

Income Shares states (38 + DC): Arizona, California, Colorado, Connecticut, Florida, Georgia, Idaho, Illinois, Indiana, Iowa, Kansas, Kentucky, Louisiana, Maine, Maryland, Massachusetts, Michigan, Minnesota, Missouri, Nebraska, New Hampshire, New Jersey, New Mexico, New York, North Carolina, Ohio, Oklahoma, Oregon, Pennsylvania, Rhode Island, South Carolina, South Dakota, Tennessee, Utah, Vermont, Virginia, Washington, West Virginia, Wyoming, DC. Percentage of Obligor Income (6): Alaska, Arkansas, Mississippi, Nevada, North Dakota, Wisconsin. Melson Formula (3): Delaware, Hawaii, Montana. (Texas uses a Percentage of Obligor Income variant with statutory caps.) Source: HHS Office of Child Support Services (OCSS) cross-state guideline reference.

Question 3

What income counts in the guideline?

Accepted Answer

Most state statutes define income broadly: W-2 wages, 1099 self-employment income, partnership distributions, bonuses, commissions, overtime, severance, pension/retirement distributions, Social Security disability (the parent's benefit, not the child's auxiliary), workers' comp, unemployment, alimony received from a prior relationship, and imputed income if the parent is voluntarily unemployed or underemployed. State statutes vary on whether to include: in-kind benefits (housing, car), means-tested benefits (TANF, SNAP — usually excluded), capital gains (varies), and gifts. Cross-state variance is biggest on imputed income — some states aggressively impute earning potential based on prior earnings or BLS occupational wage data, others require proof of actual income.

Question 4

How are deviations from the guideline calculated?

Accepted Answer

All 50 states allow judicial deviation from the guideline figure, but the standards differ. Most states require: (a) a finding that the guideline result would be 'unjust or inappropriate,' (b) factual basis for the deviation on the record, and (c) the deviation amount + reason in writing. Common deviation factors: high obligor income (some states cap or step down at the high end), shared physical custody (overnights), extraordinary medical needs, private school tuition, travel costs for visitation, special needs children, and the relative wealth of the custodial parent's household. This calculator does NOT model deviations — it produces the baseline guideline number from which deviations are negotiated or litigated.

Question 5

How does shared physical custody change the calculation?

Accepted Answer

Most state guidelines reduce support obligations when overnights exceed a threshold — typically 92, 110, or 128 nights per year depending on state. Below the threshold, full guideline support applies. Above, states use varying formulas: some use a sliding-scale reduction, some use a cross-credit method (each parent calculates support as if the other had primary custody, then the higher pays the difference), some require equal-shared-time orders to fall outside the guidelines entirely. The exact threshold and reduction mechanic is one of the most-state-specific parts of the calculation. Consult your state's child-support guideline statute or worksheet.

Question 6

How are health insurance premiums and childcare costs handled?

Accepted Answer

Most state guidelines treat health insurance premiums for the children (the child's share, not the parent's) and work-related childcare costs as 'add-ons' to the basic guideline amount. They're typically apportioned between parents in proportion to combined income (under Income Shares) or paid by the obligor on top of the guideline amount (under Percentage of Obligor Income). The exact treatment is state-specific. Cash medical support (separate from premiums — covers uninsured medical expenses) is also typically apportioned by income share with a deductible threshold.

Question 7

Can this calculator replace a family-law attorney?

Accepted Answer

No. This is a math estimator. Real support orders require: court filing, exchange of financial affidavits, possible discovery on income, hearing on the petition, and entry of an order by the judge. Modifications require a substantial change in circumstances. Enforcement (wage garnishment, contempt, license suspension) is handled by the state child-support enforcement agency under federal Title IV-D. An attorney is essential for: contested cases, high-income obligors, self-employed obligors where income is disputed, shared-custody disputes, deviations from the guideline, and any interstate enforcement under UIFSA (Uniform Interstate Family Support Act).

Question 8

How often should I update this calculation?

Accepted Answer

State guideline tables are periodically reviewed (federal requirement under 45 CFR §302.56 mandates 4-year review of guidelines). Income figures should be re-run whenever a parent's income changes substantively — courts generally require a 'substantial change in circumstances' (often 10–20% income change or 3 years) to modify an existing order. Tax law changes affect imputed income calculations (e.g., 2017 TCJA changed alimony tax treatment for post-2018 agreements, which indirectly affects some states' adjusted-gross-income definitions in the child-support context).

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