Child support · DE
Delaware child support calculator
How the Family Court of Delaware turns two gross incomes into one order, line by line on Form 509.
Rules read on official Delaware pages on · Checked by Radif Partners · How we calculate
- Model
- Melson formula
- Income counted
- Gross income
- Shared parenting
- No fixed formula
- 1 child, $5,000 / $3,000
- $907
- a month
A Delaware parent earning $4,000 a month gross, with the other parent at $2,000 and one child living with that parent, owes about $892 a month under the formula the Family Court revised on February 1, 2026. Delaware invented the Melson formula and still applies it through Family Court Civil Rules 500 to 510. Every parent first keeps a self-support allowance of $1,600 a month. The remaining income sets each parent's share of the child's primary need, which starts at $800 for the first child and adds $420 for each additional one, plus work-related child care and part of the children's medical premium. Whatever income survives that step feeds the standard of living adjustment: 12% for one child, 17% for two, 21% for three. The order is capped at 50% of the parent's net available income and, outside shared placement, cannot fall below $160 for one child.
Guideline child support in Delaware, per month
$907
$10,884 a year
| Income after the self-support allowance (paying parent) | $3,400 |
| Paying parent’s share of net available income | 70.8% |
| Total primary need, 1 child | $800 |
| Standard of living adjustment (12 %), paying parent | $340 |
| Net monthly obligation (Line 24) | $907 |
Estimate under the Delaware guideline as published, from the incomes you enter. Deviations, imputed income, other children and the judge's findings can change the order. How this is calculated.
The Melson formula at home
Judge Elwood Melson's method was built in Delaware's Family Court, and the 2026 version keeps its three layers: protect the parent, cover the child's primary need, then share the standard of living. The allowances are reset by February 1 of every year from the federal poverty guidelines, which is why Form 509i carries a year in its title. With $4,000 of gross pay, Line 6 leaves $2,400 after the $1,600 allowance; a parent at $2,000 keeps $400. That puts 85.7% of the primary need on the higher earner.
Income is gross, but not every dollar counts the same. Nontaxable income such as VA benefits or post-2018 alimony is raised by 25% to reach a taxable equivalent, and a parent who is unemployed without good cause is imputed at least the presumptive minimum income of $2,390 a month.
Overnights: two steps, then half a child
Line 22 rewards regular contact. A parent with 80 to 124 overnights a year keeps 10% of the other household's retained primary support and SOLA; from 125 overnights it is 30%. In our example the order goes from $892 to $788 at 100 overnights and $580 at 140. From 164 overnights in each home the child counts as half a child in each household, the half-child allowance of $590 applies on both sides, and the two obligations offset each other: $490 a month at an even split. Nothing is owed in shared placement when the result is under $50.
Where the floor and the ceiling meet
Line 23 limits any order to 50% of the parent's net available income, 35% when the parent supports children in three or more households. The minimum order then pushes back up: a parent earning $1,800 next to a parent earning $3,000 would be capped below the minimum, yet the court imposes $160 for one child unless the parent is disabled. For two children at our main incomes the formula lands on $1,200, held there by that same Line 23 ceiling. When both parents keep more than $16,000 for SOLA, 30% of the excess is set aside before the SOLA percentage applies.
The court's Child Support Calculator and Form 509i instructions are the reference. For the same model in another state, see Hawaii.
The Delaware guideline this calculator applies
| Rule | Delaware |
|---|---|
| Model | Delaware Child Support Formula (Melson): self-support allowance, primary support allowance, standard of living adjustment (Family Court Civil Rules 500-510) |
| Income counted | Gross income before taxes, as the state guideline defines it. |
| Shared parenting | No overnight formula in the calculator (see the rule below) |
Monthly support for one paying parent, the other parent without income
| Paying parent’s monthly income | 1 child | 2 children | 3 children | 4 children |
|---|---|---|---|---|
| $2,000 | $200 | $240 | $240 | $240 |
| $3,000 | $700 | $700 | $700 | $700 |
| $4,000 | $992 | $1,200 | $1,200 | $1,200 |
| $5,000 | $1,112 | $1,591 | $1,700 | $1,700 |
| $6,000 | $1,232 | $1,761 | $2,200 | $2,200 |
| $8,000 | $1,472 | $2,101 | $2,640 | $3,058 |
| $10,000 | $1,712 | $2,441 | $3,060 | $3,518 |
| $12,500 | $2,012 | $2,866 | $3,585 | $4,093 |
| $15,000 | $2,312 | $3,291 | $4,110 | $4,668 |
| $20,000 | $2,854 | $4,080 | $5,112 | $5,795 |
How the amount is set. Line 6 = gross (+25% of nontaxable) - SE adjustment - deductions - $1,600. Line 8 = Line 6 x (100% or 70% if other dependents). Line 9 share = Line 8 / total Line 8. Line 11 primary support allowance per household by children living there ($800 first child, +$420 each additional; $590 for a half child, +$210 each additional half). Line 13 total primary need = allowances + child care + allowable tuition + children's medical premiums (x75%, or 50% if other dependents). Line 14 = Line 9 x Line 13. Line 15 = Line 8 - Line 14 (>=0). Line 16 high-income offset = 30% x sum of each parent's (Line 15 - $16,000, >=0). Line 18A SOLA = (Line 15 - Line 16B) x SOLA% (12% 1 child, 17% 2, 21% 3, +2% each additional). Line 19 = Line 14 + Line 18A. Line 24 net obligation = Line 19 - retained primary and SOLA (Line 20) - child care/tuition paid (Line 21) - parenting time adjustment (Line 22B), capped at 50% of Line 8 (35% if supporting children in 3+ households) (Line 23). All amounts monthly, rounded to the nearest whole dollar. source
Income. Monthly gross income (wages, secondary income case by case, overtime, other taxable income, self-employment, nontaxable income such as post-2018 alimony, VA benefits and military allowances) plus a 25% surcharge on nontaxable income (Line 2), less 7% of documented self-employment income (Line 3), allowable deductions (mandatory pension, voluntary retirement up to 5% of gross, union dues, disability insurance, medical insurance not covering these children, court-ordered alimony) and the $1,600 self-support allowance; x 70% if the parent supports other dependent children (Lines 1-8). Reasonable earning capacity is used; presumptive minimum income is $2,390 per month (Form 509i, 2026).
Parenting time. A child living more than 163 overnights in each home counts as 1/2 child in each household (Line 10) and each household gets the half-child primary allowance ($590, +$210). For 80-124 overnights the obligated parent retains 10%, for 125-163 overnights 30%, of the other parent's retained primary support and SOLA (Line 22). In shared or split placement no obligation is assessed below $50 per month (Line 24) (Form 509i, 2026).
Child care and health care. Actual work-related child care is part of total primary need (Line 12A) and shared by Line 9 share; each parent is credited for what it pays (Line 21). Premiums for policies covering the children enter Line 12C at 75% (50% if the parent supports other children); coverage costing more than 10% of income is presumed unaffordable. Uninsured medical costs are split by Line 9 share rounded to the next 10% toward 50% (Line 25). Child care, allowable private school tuition and children's medical premiums are added to primary need (Line 12).
Low incomes. Each parent receives a $1,600 monthly self-support allowance (Line 5). The obligation cannot exceed 50% of Line 8 (35% if the parent supports children in 3 or more households) (Line 23). Unless placement is shared or split or the payer is disabled, the minimum order is $160 for one child and $240 for more than one (Form 509i, 2026).
The state also runs its own official child support calculator; use it, or the court's worksheet, for a filing.
Worth knowing in Delaware
- Delaware revised its formula effective February 1, 2026; monetary allowances are adjusted by February 1 each year with the HHS poverty guidelines and the whole formula is to be reviewed again in 2026 (Form 509i). source
- Nontaxable income such as VA benefits is grossed up by 25% to its taxable earned-income equivalent (Line 2). source
- In a new support petition, 6 months of retroactive support before filing is presumed, never more than 2 years (Form 509i). source
- Within 2 1/2 years of the last order, a modification needs a particularized substantial change and a change of more than 10%; a formula revision alone is not a ground (Form 509i). source
- Arrears are presumptively repaid at 20% of current support, at least $20 per month (Form 509i). source