SSDI eligibility starts with work credits — what they are, how many you need at your age, and what to do if you don’t have enough.
What a work credit is
Social Security work credits are earned by working and paying Social Security taxes. You can earn up to four credits per year, and the earnings required per credit adjusts annually — the current amounts are published by the Social Security Administration. Credits never expire for retirement, but SSDI adds a recency requirement.
The general rule: 40 credits, 20 recent
Most workers need 40 credits total, with 20 earned in the 10 years before disability began — the "20/40 rule." In practice that means roughly five of the last ten years working. This is also why waiting to apply can be dangerous: your insured status can lapse.
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Request your free case review →Younger workers need fewer
The SSA scales the requirement by age. Workers disabled before 24 may qualify with 6 credits in the prior 3 years; between 24 and 31, credits for half the time since age 21. The full schedule is on the SSA’s disability site.
Your date last insured (DLI)
When you stop working, your SSDI coverage doesn’t end immediately — it ends at your date last insured. If your disability began before your DLI, you can still win benefits even if you apply after it. Proving disability onset before a past DLI is one of the most evidence-intensive things we do.
No credits? SSI is the other path
If you don’t meet the credit test, Supplemental Security Income uses the same medical standard with no work-history requirement — it is need-based instead. We routinely file SSDI and SSI concurrently when the facts support both.
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