Calculation is client-side, income figures are never transmitted or stored.
How Alabama Child Support Is Calculated
- Combine both parents' gross monthly incomes to get combined adjusted gross income.
- Look up the basic child support obligation from the official Schedule of Basic Child-Support Obligations for that combined income and number of children (below $800/month combined, a flat $50 minimum applies).
- Each parent's share equals their income divided by the combined income, applied to the basic obligation.
- If a parent has roughly 143-164+ overnights/year, a separate Shared Physical Custody worksheet applies instead of straight proration.
- Above $20,000/month combined income, courts determine support case-by-case.
Alabama Child Support Worksheet Walkthrough
Example: combined gross income $3,000/month, 2 children, Parent A earns $1,800/mo (60% share), Parent B earns $1,200/mo (40% share) and has primary custody.
- Basic child support obligation for $3,000 combined, 2 children: $837/month.
- Parent A's share: 60% × $837 = $502/month guideline child support paid by Parent A.
How This Calculator Works — Formula & Constants
Source: Alabama Rules of Judicial Administration, Rule 32 (Alabama Supreme Court) · Calcul déterministe — no AI, no arbitrary estimate.
Constants used
| Constant | Value | Source |
|---|---|---|
| Self-support reserve | $981/mo | Ala. R. Jud. Admin. 32 |
| Overnights threshold | 143 nights/yr | Ala. R. Jud. Admin. 32 |
Formula
base_obligation = schedule_lookup(combined_income, children)
share_B = parentB_income / combined_income
total_obligation = base_obligation + childcare_cost + health_insurance_cost
obligation_B = total_obligation × share_B
obligation_B = obligation_B × (1 - custody_credit(overnights))
Deterministic calculation based on Alabama's official guideline schedule table. Verify against Alabama's official calculator for a court-ready figure.
FAQ
How is child support calculated in Alabama?
Combine both parents' gross monthly incomes to get combined adjusted gross income. Look up the basic child support obligation from the official Schedule of Basic Child-Support Obligations for that combined income and number of children (below $800/month combined, a flat $50 minimum applies). Each parent's share equals their income divided by the combined income, applied to the basic obligation. If a parent has roughly 143-164+ overnights/year, a separate Shared Physical Custody worksheet applies instead of straight proration. Above $20,000/month combined income, courts determine support case-by-case.
Does Alabama reduce child support for shared custody?
Only through a separate track, not an automatic reduction. If a parent has roughly 143 to 164 or more overnights per year, Alabama requires a distinct Shared Physical Custody worksheet instead of straight proration of the basic obligation. The exact mechanics of that worksheet's adjustment weren't independently re-verified in this project's sourcing pass, so treat this calculator's standard estimate as a starting point if your case is near that overnight threshold.
What is Alabama's self-support reserve?
Alabama's self-support reserve is $981/month. It functions as a floor — Rule 32 guidelines are designed so a paying parent's own income generally isn't reduced below this level by a child support order, similar in purpose to the self-support reserves used in several other income-shares states.
What happens if combined income is above $20,000/month?
Alabama's official schedule extends to $20,000/month in combined gross income. Above that, the guidelines don't specify a table value, and courts determine the appropriate amount case-by-case rather than extrapolating the percentage automatically.
Methodology & Source
Formula model: income shares. Effective 2022-05-01, guideline version 2022-AL-v1, last reviewed 2026-07-11.
Official source: Alabama Rules of Judicial Administration, Rule 32 (Alabama Supreme Court) (Ala. R. Jud. Admin. 32).
Courts may deviate from the guideline amount for documented reasons — this calculator shows the presumptive guideline amount only, not a court order. Above $20,000/month combined income, courts determine support on a case-by-case basis.
Guideline figures transcribed from the primary source above and cross-checked against Alabama's official calculator/worksheet for multiple test scenarios — see our verification methodology.