Child Support Calculations in Maryland

Maryland uses the Income Shares model to calculate child support, governed by Md. Code, Family Law §12-204 and the Maryland Child Support Administration. The schedule was expanded effective July 1, 2022, to cover combined monthly incomes up to $30,000. Whether you're navigating an uncontested or contested divorce, understanding how Maryland calculates child support is essential.

The Income Shares Model

Maryland's Income Shares model determines the Basic Child Support Obligation from the statutory schedule based on combined adjusted actual monthly income and the number of children. The schedule provides amounts at income increments up to a combined income of $30,000/month.

Above the cap: If combined adjusted income exceeds $30,000/month, the court may use its discretion to set support, considering the schedule's marginal rates, the children's reasonable needs, and the parents' circumstances.

Determining Actual Income

"Actual income" includes income from any source:

• Wages, salaries, commissions, bonuses, and overtime
• Self-employment income (gross receipts minus ordinary/necessary expenses)
• Dividends, interest, trust income, pensions, and annuities
• Social Security benefits, workers' comp, unemployment, and disability
• Alimony received (alimony paid is deducted)
• In-kind reimbursements that reduce personal living expenses

Excluded: Means-tested benefits (SSI, TANF, SNAP) are excluded from actual income.

Imputation: If a parent is "voluntarily impoverished," courts may impute potential income based on statutory factors including age, education, skills, employment history, and local job market conditions. Courts cannot impute income to a parent who is disabled or caring for a child under age 2.

Shared Physical Custody (25% Threshold)

Maryland uses a 25% overnight threshold (≥92 nights) for shared physical custody, which triggers a specialized calculation:

• 1.5× multiplier: The basic obligation is multiplied by 1.5 for shared custody
• Cross-multiplication: Each parent's share is multiplied by the other parent's percentage of overnights
• Net payment: The parent with the greater theoretical amount pays the difference

25-30% adjustment bands: If a parent has between 25% and 30% of overnights (92-109 nights), an additional percentage is added to their theoretical obligation:

• 92-94 nights (25-26%): +10%
• 95-98 nights (26-27%): +8%
• 99-102 nights (27-28%): +6%
• 103-105 nights (28-29%): +4%
• 106-109 nights (29-30%): +2%

Estimate Your Maryland Child Support

Use our calculator to get a preliminary estimate. For official calculations, use the Maryland Rule 9-206 worksheets (Worksheet A for sole custody, Worksheet B for shared custody).

Self-Support Reserve and Low-Income Cases

Maryland protects low-income obligors through the Self-Support Reserve (SSR):

• SSR amount: Approximately $1,145/month (110% of the 2019 federal poverty guideline for one person)
• Schedule notation: Low-income entries affected by the SSR are marked with asterisks in the statutory schedule
• Minimum amounts: The schedule's lowest row (combined income $0-$1,200) yields $50 for one child

Add-Ons: Childcare, Health Insurance, and Medical

Beyond the basic obligation, Maryland adds these expenses (shared proportionally by income):

• Work-related childcare: Actual costs for employment or job search
• Health insurance: The child's portion of premiums
• Extraordinary medical: Uninsured expenses exceeding $250 per child per year
• Education/transportation: By agreement or order, private school for particular needs and transportation between homes

Common Calculation Mistakes

• Wrong custody threshold: Shared custody applies at 25% (92 nights), not 35%
• Forgetting the 1.5 multiplier: Shared custody always uses 1.5× the basic obligation
• Missing the 25-30% adjustment: Add 2-10% to the theoretical obligation when between 92-109 nights
• Extrapolation errors: When income falls between schedule rows, use the next higher amount
• Ignoring the shared-custody cap: Support cannot exceed what would be owed under sole custody

Modification and Duration

Maryland provides pathways to modify support:

• Material change: Required by statute; guideline revisions alone are not a material change
• Practical threshold: A ~25% change in income is often sufficient
• 36-month review: The Child Support Administration reviews cases every 3 years on request
• Specific conditions: Incarceration, permanent disability, or institutionalization qualify as material changes

Duration: Support ends at age 18. If the child is still enrolled in secondary school at 18, support continues until graduation or age 19, whichever comes first. Maryland also provides for "destitute adult child" support under Family Law Title 13 for children who cannot be self-supporting due to disability.

Enforcement and Interest

Maryland provides robust enforcement tools:

• Interest on judgments: 10% per year simple interest once arrears are reduced to judgment (not automatic)
• Income withholding: Immediate and standard; up to CCPA limits (50-65%)
• Federal tax offset: When arrears ≥$500 and ≥2 months overdue
• State tax intercept: When arrears ≥$150 and ≥2 months overdue
• Passport denial: When arrears exceed $2,500
• License suspension: Driver's (60+ days), professional (120+ days)

Key Takeaways

• Income Shares model: Basic obligation from schedule, allocated by income shares
• $30,000/month cap: Court discretion applies above this threshold
• 25% shared custody threshold: 92+ overnights triggers 1.5× multiplier
• 25-30% adjustment bands: Add 2-10% for parents with 92-109 nights
• SSR protection: ~$1,145/month ensures obligors retain basic income
• Support to age 19: If still in high school at 18
• 10% judgment interest: On arrears reduced to judgment (not automatic)

For more information about Maryland divorce processes, see our Maryland divorce timeline and filing checklist.