- Family income and the severity of the disabled child's condition must meet SSI guidelines to qualify for an income benefit of $674 for 2011. To receive this amount, a couple cannot have monthly wage earnings over $2,107. States contribute support for this program through revenue sharing. Income payments may be different in other states. The SSA says a child under age 18 must have a "medically determinable physical or mental impairment, which results in marked and severe functional limitations and can be expected to result in death or has lasted or can be expected to last for a continuous period of not less than 12 months."
- Workers qualify for disability income benefits under SSDI by accumulating 40 quarters of work history and satisfying the disability definition. In 2011, one quarter equals $1,120 of recorded earnings; four quarters are the maximum number of quarters allowed per year. A disabled child will receive benefits only if one of his parents is a fully insured worker and the parent is now either deceased or receiving Social Security retirement or disability income. The monthly payment will be based on a percentage of what the parent is entitled to according to the parent's work record. As long as the disabled child remains a dependent and disabled, the monthly payment will continue indefinitely.
- Unlike Supplemental Security Income, SSDI is potentially taxable depending on how much other income the supporting parent receives. For example, if she is filing as head of household and has more than $25,000 modified adjusted gross income (MAGI), up to 50 percent of the SSDI for her disabled child may be taxable. MAGI above $34,000 subjects up to 85 percent of SSDI to tax. For joint filers, the income thresholds are $32,000 and $44,000, respectively. MAGI is calculated by adding one-half of all Social Security income plus all other income, including tax-free interest.
- Supplemental Security Income stops at age 18, but SSDI continues because of the parent's original qualification for Social Security child benefits as a fully insured deceased, retired or disabled worker. Now an adult, the individual will continue to receive benefits under the system based on the adult definition of disability and earnings restrictions. Participants are encouraged to enter work training programs and seek employment suitable for their circumstances. Currently, monthly earnings in excess $1,000, or $1,640 if blind, would be considered "substantial" and may reduce or end disability payments.