Calculation is client-side, income figures are never transmitted or stored.
How Hawaii Child Support Is Calculated
- Hawaii uses a Modified Melson Formula -- one of only 3 states (with Delaware and Montana) that use this model, though Hawaii's version differs from Delaware's in several ways.
- Net Income for each parent is gross income minus taxes (2022 federal/state/FICA tables, single filer) and the Self-Support Reserve ($1,693/month, 130% of the one-person federal poverty guideline).
- The Primary Child Support Need is a flat $455 per child (no separate per-household allowance, unlike Delaware), plus childcare and health insurance costs, prorated by each parent's share of combined Net Income.
- SOLA Income for each parent is gross income minus $1,303 (a separate, smaller deduction than the Self-Support Reserve). The combined SOLA Income minus the Primary Need is the pool shared with the children, at a flat 10% per child, capped at 30% (unlike Delaware's tiered 12/17/21%).
- The paying parent's obligation generally may not exceed their own Net Income, and a minimum of $91/child/month applies.
- Extensive Time-Sharing and Equal Time-Sharing use separate worksheets with different calculations, not modeled here.
Hawaii Child Support Worksheet Walkthrough
Example: Parent A earns $2,500/mo, Parent B earns $2,000/mo, 3 children, Parent A is the noncustodial parent.
- Net Income (this calculator's approximation, Self-Support Reserve only): Parent A = $2,500 - $1,693 = $807. Parent B = $2,000 - $1,693 = $307. Combined = $1,114.
- Primary Need: 3 × $455 = $1,365. Parent A's share (807/1,114 = 72.4%): ≈$989 -- but capped at Parent A's own Net Income of $807.
- SOLA Income: Parent A = $2,500-$1,303=$1,197. Parent B = $2,000-$1,303=$697. Combined $1,894, remaining after Primary Need ($1,365) = $529. SOLA % for 3 children = 30% (capped): $159 SOLA amount.
- Parent A's total theoretical obligation exceeds their own Net Income, so it caps at $807/month.
How This Calculator Works — Formula & Constants
Source: Hawai'i State Judiciary (2024 Child Support Guidelines, RG-AC-508) · Calcul déterministe — no AI, no arbitrary estimate.
Constants used
| Constant | Value | Source |
|---|---|---|
| Self-Support Reserve | $1,693/mo | HRS §§ 571-52.5, 576D-7 |
| Base Primary Support, per child | $455 | HRS §§ 571-52.5, 576D-7 |
| SOLA income deduction | $1,303/mo | HRS §§ 571-52.5, 576D-7 |
| SOLA %, per child (capped) | 10% per child, max 30% | HRS §§ 571-52.5, 576D-7 |
| Minimum order | $91/child/mo | HRS §§ 571-52.5, 576D-7 |
Formula (Hawaii's Modified Melson Formula)
share(parent) = Net Income(parent) / combined Net Income
Primary Need = children × Base Primary Support + childcare + health insurance
SOLA Income(parent) = max(0, gross_income(parent) - SOLA income deduction)
Remaining SOLA = max(0, combined SOLA Income - Primary Need)
SOLA Amount = Remaining SOLA × min(30%, 10% × children)
support = min(paying parent's Net Income, paying parent's share × (Primary Need + SOLA Amount))
Deterministic calculation based on Hawaii's Modified Melson Formula. Verify against Hawaii's official CSG Worksheet for a court-ready figure.
FAQ
How is child support calculated in Hawaii?
Hawaii uses a Modified Melson Formula -- one of only 3 states (with Delaware and Montana) that use this model, though Hawaii's version differs from Delaware's in several ways. Net Income for each parent is gross income minus taxes (2022 federal/state/FICA tables, single filer) and the Self-Support Reserve ($1,693/month, 130% of the one-person federal poverty guideline). The Primary Child Support Need is a flat $455 per child (no separate per-household allowance, unlike Delaware), plus childcare and health insurance costs, prorated by each parent's share of combined Net Income. SOLA Income for each parent is gross income minus $1,303 (a separate, smaller deduction than the Self-Support Reserve). The combined SOLA Income minus the Primary Need is the pool shared with the children, at a flat 10% per child, capped at 30% (unlike Delaware's tiered 12/17/21%). The paying parent's obligation generally may not exceed their own Net Income, and a minimum of $91/child/month applies. Extensive Time-Sharing and Equal Time-Sharing use separate worksheets with different calculations, not modeled here.
How is Hawaii's Melson Formula different from Delaware's?
Both use the same 3-step Melson concept (self-support first, then primary need, then a Standard of Living Adjustment), but the specific numbers differ: Hawaii's Base Primary Support is a flat $455/child with no separate per-household allowance, while Delaware adds a per-household component. Hawaii's SOLA is a flat 10% per child capped at 30%, while Delaware uses tiered percentages (12%/17%/21%) plus a High Income Offset that Hawaii doesn't have.
What is Hawaii's Self-Support Reserve?
The Self-Support Reserve is $1,693/month (130% of the one-person federal poverty guideline), subtracted from a parent's income before calculating their Net Income for child support purposes. Hawaii's official calculation also subtracts actual income taxes using 2022 tax tables -- this calculator approximates Net Income using only the Self-Support Reserve deduction, so its result may run somewhat higher than an official calculation.
Is there a minimum or maximum child support amount in Hawaii?
The minimum is $91 per child per month. The paying parent's obligation generally should not exceed their own monthly Net Income, if that Net Income exceeds $91 per child -- a cap built directly into the calculation, not left to judicial discretion.
Methodology & Source
Formula model: hi melson. Effective 2024-04-01, guideline version 2024-HI-v1, last reviewed 2026-07-13.
Official source: Hawai'i State Judiciary (2024 Child Support Guidelines, RG-AC-508) (HRS §§ 571-52.5, 576D-7).
This calculator approximates Hawaii's official 'Net Income' by subtracting only the Self-Support Reserve ($1,693/mo) from gross income -- the real Table of Incomes (Appendix B) also subtracts actual 2022 federal/state tax tables for a single filer with one exemption, which this calculator does not reproduce, so the modeled Net Income runs somewhat HIGHER than the official figure. Extensive Time-Sharing and Equal Time-Sharing worksheets (materially different calculations for shared custody) and the Cash Medical Support alternative (10% of net income when no insurance is available) are not modeled.
Guideline figures transcribed from the primary source above and cross-checked against Hawaii's official calculator/worksheet for multiple test scenarios — see our verification methodology.