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Updated March 22, 2018
Social Security Disability Insurance (SSDI)
What is SSDI?
How Many People Are on SSDI and How
Social Security Disability Insurance (SSDI) is a federal
Much Do They Receive?
social insurance program that provides monthly cash
In January 2018, 10.4 million individuals received SSDI
benefits to nonelderly disabled workers and their eligible
benefits, including 8.7 million disabled workers, 124,000
dependents, provided the worker paid into the system for a
spouses of disabled workers, and 1.6 million children of
sufficient number of years. The program is part of Old-Age,
disabled workers (Table 1).
Survivors, and Disability Insurance (OASDI), commonly
known as Social Security. As with Old-Age and Survivors
Table 1. Number of SSDI Beneficiaries and Average
Insurance (OASI)—the retirement component of Social
Benefit Levels, by Type, January 2018
Security—benefits are based on a worker’s past earnings in
covered employment. The Social Security Administration
Total
(SSA) administers both SSDI and OASI.
Average
Monthly
Number
Monthly
Benefits
Who is Eligible for SSDI?
Beneficiary
(thousands)
Benefit
(millions)
To qualify for SSDI, workers must be (1) insured in the
Total
10,391
$1,060
$11,013
event of disability, (2) statutorily disabled, and (3) under
Social Security’s full retirement age (FRA), which is 65-67,
Disabled
8,677
$1,197
$10,388
depending on year of birth. To achieve insured status,
Workers
individuals must have worked in jobs covered by Social
Spouses
124
$336
$42
Security for about a quarter of their adult lives and for at
least five of the 10 years prior to the onset of disability.
Children
1,589
$367
$584
However, younger workers may qualify with less work
Source: Social Security Administration (SSA), “Monthly Statistical
experience based on their age. In 2017, SSDI provided
Snapshot, January 2018,” February 2018, Table 2.
disability insurance coverage to 154 million workers; about
89% of covered workers aged 21-64 were insured for SSDI.
Cash benefits begin five full months after a worker’s
disability onset date. This requirement is known as the five-
To meet the statutory test of disability, insured workers
month waiting period. Initial benefits are based on a
must be unable to engage in any substantial gainful activity
worker’s career-average earnings in covered employment,
(SGA) due to any medically determinable physical or
indexed to reflect changes in national earnings levels. The
mental impairment that is expected to last for at least one
benefit formula is progressive, replacing a greater share of
year or to result in death. SSA uses a monetary threshold to
career-average earnings for low-wage workers than for
determine whether an individual’s work activity constitutes
high-wage workers. Initial benefits may be offset if a
SGA, which is adjusted annually for earnings growth. In
disabled worker also receives state workers’ compensation
2018, the SGA earnings limit for most workers is $1,180
or certain other public disability benefits. SSDI benefits are
per month. In general, workers must have a severe
subsequently adjusted to account for inflation through cost-
impairment (or combination of impairments) that prevents
of-living adjustments (COLAs). In January 2018, the
them from doing any kind of substantial work that exists in
average monthly benefit for a disabled worker was $1,197
significant numbers in the national economy, taking into
(Table 1). On an annualized basis, the average disabled-
consideration their age, education, and work experience.
worker benefit is $14,364, which is about 118% of the
The work need not exist in the immediate area in which the
federal poverty level (FPL) for an individual.
claimant lives, nor must a specific job vacancy exist for the
individual. (SSDI does not pay benefits for partial or short-
In addition to cash benefits, disabled workers and certain
term disabilities.)
disabled dependents are eligible for health coverage under
Medicare after 24 months of entitlement to cash benefits
Some family members are also eligible for benefits, subject
(generally 29 months after the onset of disability). This
to maximum family benefit rules.
requirement is known as the 24-month waiting period and
does not apply to workers with amyotrophic lateral sclerosis
Spouses may qualify if they are (1) aged 62 or older or
(ALS) or end-stage renal disease (ESRD). Due in part to
(2) any age and care for an eligible child who is under
this waiting period, only 68% of disability beneficiaries
age 16 or disabled.
under age 65 reported entitlement to Medicare in 2016.
Medicare spending per disabled beneficiary under age 65
Children may qualify if they are unmarried and (1)
was about $12,776 in 2013 (excludes ESRD beneficiaries).
under age 18, (2) aged 18-19 and in school, or (3) aged
Medicare is not provided to non-disabled dependents under
18 or older and became disabled before age 22 and
age 65.
remain so.
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Social Security Disability Insurance (SSDI)
When Do Benefits Stop?
Does SSA Review the Medical Status of
In general, disabled workers continue to receive SSDI
Beneficiaries?
benefits until they (1) die, (2) attain FRA, (3) medically
SSA periodically reevaluates a beneficiary’s disability
improve, or (4) return to work (i.e., earn above the monthly
status by conducting a continuing disability review (CDR).
SGA limit). Most disabled workers who leave the rolls do
The frequency of a CDR depends on the beneficiary’s
so because they attain FRA, which is the age at which
likelihood of medical improvement; most disabled workers
unreduced Social Security retired-worker benefits are first
are scheduled to receive a review once every three years.
payable. Disabled workers are transitioned automatically at
Under current law, SSA must find substantial evidence of
FRA from SSDI to OASI; however, this change generally
medical improvement during a CDR to find a SSDI
does not affect the amount of Social Security benefits paid
beneficiary no longer disabled. The average savings-to-cost
to them or their dependents.
ratio of a CDR over a 10-year period is $9 to $1. About
0.4% of disabled workers leave the SSDI rolls each year
Are Beneficiaries Allowed to Work?
due to medical improvement. SSA also performs work
Yes. SSDI beneficiaries are afforded a trial work period
CDRs to determine if a beneficiary is earning above the
(TWP) during which they may test their ability to work and
SGA limit and if eligibility for benefits should continue.
earn any amount for up to nine months (not necessarily
consecutive) within a 60-month rolling period without
Characteristics of SSDI Beneficiaries
having their benefits reduced or terminated. In 2018, any
SSDI provides benefits primarily to older workers; in
month in which earnings exceed $850 is considered a
December 2016, 75% of disabled workers were aged 50 or
month of services (i.e., work) and counted toward the
older. The most common type of impairment among
beneficiary’s nine-month TWP. Following the exhaustion
disabled workers aged 50 or older was musculoskeletal
of the TWP, disabled workers enter a 36-month extended
(i.e., conditions related to muscles, ligaments, tendons, and
period of eligibility (EPE), during which their benefits are
bones; Figure 1). The common type of impairment among
reinstated for months in which their earnings are within the
disabled workers under age 50 was mental.
SGA limit. Disabled workers who earn above the SGA limit
after the EPE are generally terminated from the program;
Figure 1. Disabled Workers, by Diagnostic Group and
however, they retain Medicare coverage for at least 57
Age, December 2016
months following the EPE (or at least 93 months following
the TWP), provided they continue to have a qualifying
impairment. About 0.5% of disabled workers leave the
SSDI rolls each year due to earnings above the SGA limit.
How is the Program Financed?
Benefits and administrative costs for SSDI and OASI are
financed primarily by payroll taxes levied on the earnings
of covered workers, which are deposited into the Disability
Insurance (DI) and Old-Age and Survivors Insurance
(OASI) trust funds. The combined Social Security payroll
tax rate is 12.4% of a worker’s earnings (6.2% for
employers and employees, each), up to a maximum annual
amount, which for 2018 is $128,400. The trust funds also
receive income from the taxation of a portion of some
Social Security benefits and from interest earned on U.S.
securities credited to the trust funds for years in which
income exceeded cost.
Source: SSA, Annual Statistical Report on the Social Security Disability
Insurance Program, 2016, Table 24.
In 2017, total income to the Social Security trust funds was
$997 billion, with $171 billion (or 17%) credited to the DI
SSDI benefits are an important source of income to
trust fund. That same year, total outlays from the trust funds
disabled workers and other Social Security beneficiaries
were $952 billion, with $146 billion (or 15%) coming from
who receive benefits due to a disability. In 2016, SSDI
the DI trust fund. The trust funds held a combined $2.9
benefits made up more than half of personal income for
trillion in asset reserves at the end of 2017, with $71 billion
84% of all disability beneficiaries and were the only source
(or 2%) credited to the DI trust fund.
of personal income for 44% of all disability beneficiaries.
More than half of all disability beneficiaries in 2016 had
The Social Security trustees project that under current law,
family income below 200% of FPL and about 23% had
the trust funds on a combined basis would be able to pay
family income below 100% of FPL.
benefits in full and on time until 2034. Individually, the DI
trust fund is projected to be depleted in 2028 and the OASI
trust fund in 2035. Upon depletion, continuing revenues to
William R. Morton,
the DI trust fund would be sufficient to pay about 93% of
IF10506
benefits scheduled under law, declining to 82% by 2091.
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Social Security Disability Insurance (SSDI)
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