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Social Security Disability Insurance (SSDI)
Since 1956· Government program
Law or rule (2026)Set by statute, regulation or the agency; numbers change yearly.
Social Security's insurance for workers who can no longer work because of a severe, long-lasting medical condition.
See it on the Personal Finance & Estate map →How it works
Created in 1956, SSDI pays your full Social Security benefit early if a condition keeps you from 'substantial gainful activity' (earning over about $1,690 a month in 2026) for at least 12 months, or is expected to be fatal. You need enough recent work credits. Payments start after a five-month wait, and Medicare follows after 24 months of benefits. Most first applications are denied, and appeals can take a year or more. At full retirement age it becomes a retirement benefit.
Why it matters for you
It protects working families against income lost to disability, a risk before retirement that is larger than many people assume, and it opens Medicare early.
Rules, limits and sources (2026)
The Social Security Amendments of 1956, expanded to all ages in 1960; SSA's disability statistics and its 'Blue Book' listing of qualifying impairments.
Watch out for
Approval standards and long waits draw criticism; the strict 'any work' test leaves many to rely on private disability insurance as well.
Connections (3)
▸Social Security Disability Insurance (SSDI) is the disability arm of Social Security (OASDI)Law or rule (2026)
How they connect
SSDI pays a disabled worker's full, unreduced benefit before retirement age, from the same earnings record and payroll taxes but through its own trust fund. At full retirement age it converts automatically into a retirement benefit.
When it applies
Created in 1956 under President Eisenhower for workers aged 50–64; the age floor was removed in 1960.
The rule
The separate Disability Insurance trust fund appears in each Trustees Report; the 2025 report projects it solvent for the full 75 years.
Watch out for
Applications have fallen since about 2010; researchers debate how much reflects a stronger job market, stricter reviews or slower processing.
▸Social Security Disability Insurance (SSDI) leads after 24 months to Medicare (federal health insurance at 65+)Law or rule (2026)
How they connect
After 24 months of SSDI payments, about 29 months after disability begins, a disabled worker gets Medicare regardless of age. People with ALS get it as soon as SSDI starts; kidney failure has separate rules.
When it applies
Congress extended Medicare to SSDI recipients in the 1972 amendments, effective 1973; the ALS exception was added in 2000.
The rule
CMS enrollment data show millions of under-65 enrollees qualifying through disability; SSA enrolls them automatically.
Watch out for
Bills to shorten or end the 24-month wait come up regularly; cost has kept them from passing.
▸Social Security Disability Insurance (SSDI) is a strict public version of Disability income insuranceStandard practice
How they connect
SSDI pays a monthly benefit based on your earnings record, but only if you can't do any substantial work (earning more than about $1,690 a month in 2026) for at least 12 months. Private disability insurance fills the gaps: looser definitions, higher benefits and a shorter wait than SSDI's five months. Most group policies subtract SSDI from what they pay.
When it applies
Congress added disability benefits to Social Security in 1956 for workers aged 50–64 and opened them to all ages in 1960.
How sure?
SSA program data show most initial claims are denied; group policy contracts spell out offsets for Social Security benefits.
Watch out for
Approval rates vary widely by state and judge, and how much SSDI discourages a return to work is debated among economists.