Child Support Calculations in Delaware

Delaware uses the Melson Formula, a unique three-step approach that protects each parent's basic needs before calculating child support. Whether you're navigating an uncontested or contested divorce, understanding the Self-Support Allowance, Primary Support, and Standard of Living Adjustment (SOLA) is essential for accurate calculations under Form 509.

The Melson Formula Explained

Delaware's Melson Formula is a variant of income shares that takes a three-step approach:

1. Self-Support Allowance (SSA): Reserves each parent's basic living needs ($1,570/month in 2025)
2. Primary Support: Covers the child's basic needs ($780 for one child)
3. SOLA: If income remains, children share in parents' higher standard of living (12-21%+ of remaining income)

The formula is a rebuttable presumption—courts use it unless applying it would be contrary to the child's best interest or unfair to the parties.

Wondering what your Delaware child support obligation might look like? Enter your details below for a quick estimate.

Now that you have an estimate, keep reading to learn about Delaware's 2025 key values, parenting-time credits, and modification rules.

2025 Key Values

From Form 509i (Rev. 2/25):

• Self-Support Allowance: $1,570/month per parent
• Primary Support Allowance: $780 for 1 child; +$410 each additional child
• Shared placement (0.5 child): $575 (+$205 per additional 0.5 child)
• SOLA percentages: 12% (1 child), 17% (2), 21% (3), +2% each additional
• High-income offset: Triggers at $15,700 available for SOLA
• Minimum order: $160 (1 child); $240 (2+ children)
• No combined income cap: SOLA offset moderates high-income obligations

What Counts as Income

Under 13 Del. C. § 514:

• Wages and salary: Including bonuses, commissions, overtime (averaged)
• Self-employment: Net business income with 7% SE tax deduction (documented)
• Benefits: SSDI (not SSI), VA benefits, military allowances
• Nontaxable income: Increased by 25% to approximate taxable equivalent
• Presumptive minimum income: $2,250/month if underemployed or undocumented

Allowable Deductions

• Mandatory pension contributions (voluntary limited to 5% of gross)
• Union dues and disability insurance premiums
• Medical insurance not covering children of this case
• Court-ordered alimony

Need a Deeper Analysis?

The calculator above gives you a quick estimate. For a comprehensive analysis covering the Melson Formula's three steps, parenting-time credits, and SOLA adjustments, get your full Delaware child support analysis here. For precise calculations, download the official Form 509 worksheet or use the Family Court's Excel calculator.

Parenting-Time Credits

Delaware provides credits based on the obligated parent's overnights:

• 0-79 overnights: No credit
• 80-124 overnights: 10% credit
• 125-163 overnights: 30% credit
• 164+ overnights: Shared placement (different calculation)

The credit is calculated by multiplying the percentage by the other parent's retained primary/SOLA amount.

Shared and Split Placement

Shared Placement (164+ Overnights Each)

• Enter 0.5 child in each household on Line 10
• The percentage credit table (10%/30%) does not apply
• If net obligation is less than $50/month, no order is imposed
• Incidental expenses (haircuts, school supplies, field trips) split equally

Split Placement

When children reside primarily with different parents:

• Enter actual child count for each household (e.g., 2 with Parent A, 1 with Parent B)
• Built-in credits offset obligations in single worksheet
• Net order under $50/month results in no payment

Add-Ons to Basic Support

• Child care: Actual work-related monthly costs (Line 12A)
• Health insurance: Premium × 75% (no other children) or 50% (other children supported); presumed unaffordable if parent+children exceeds 10% of income (Line 12C)
• Private school/tuition: May be included if prior agreement, special needs, or family history supports it (Line 12B)
• Unreimbursed medical: Allocated by percentage (Line 25), rounded to nearest 10% toward 50%

Self-Support Protection Cap

Delaware limits the maximum support obligation:

• Children in 1-2 households: Cap at 50% of Net Available for Primary Support
• Children in 3+ households: Cap at 35% of Net Available

Duration of Support

Under 13 Del. C. § 501:

• Standard termination: Age 18
• High school extension: If still in high school and likely to graduate, continues until graduation or age 19 (whichever first)
• Disabled adult children: No standard extension; limited circumstances under § 503

Modification Rules

Through Family Court or DCSS:

• Within 30 months: Must show "particularized" substantial change exceeding 10%
• After 30 months: No particularity or 10% threshold required
• Formula changes alone: Not grounds for modification
• Retroactivity: New cases: 6-month presumption (up to 24 months); modifications: back to 3 days after summons

Enforcement Tools

Delaware DCSS and Family Court employ:

• Income withholding: Automatic wage attachments
• License suspension: Driver's, hunting/fishing, professional licenses
• Tax refund intercepts: Federal and state
• Passport denial: For arrears ≥$2,500
• Bank levies and liens: Including FIDM bank matching
• Credit reporting
• Contempt proceedings: Civil contempt with potential incarceration

Interest on Arrears

Unlike many states, Delaware does not automatically add interest to child support arrears. Under 6 Del. C. § 2301, the court has discretion to award interest (generally 5% over the Federal Reserve discount rate) based on case-specific factors.

Incarceration Rules

• 180+ days continuous confinement: Evidence of diminished capacity
• Post-1/31/2019 orders: Auto-reduce to half minimum at day 181
• Pre-2019 orders: Require modification petition
• Incarcerated minimums: $80 (1 child); $120 (2+ children)

Key Takeaways

• Melson Formula: Three-step approach (SSA → Primary → SOLA)
• $1,570 SSA: Each parent's self-support reserve (2025)
• $780 Primary Support: For one child; +$410 each additional
• SOLA: 12-21%+ of remaining income after primary support
• 164-night threshold: Triggers shared placement calculation
• $160 minimum order: For one child ($240 for 2+)
• No automatic arrears interest: Court discretion required
• 30-month modification threshold: 10% change required within this period

For more information about Delaware divorce processes, see our Delaware divorce timeline and filing checklist. For property division information, review our Delaware marital property guide.