SSDI – Social Security Disability Insurance

About Social Security Disability Insurance (SSDI)

The Social Security Disability Insurance (“SSDI”) program pays benefits to individuals with qualifying disabilities who worked long enough, recently enough, and paid Social Security taxes. In other words, there are 2 parts to determining eligibility:

  1. If you are "insured" under SSDI, and
  2. If your disability is severe enough

The Difference Between SSDI and SSI

Note that SSDI is a separate program from "SSI", which stands for Supplemental Security Income.

SSI is a needs-based program; it is for people with limited income and resources who have a qualifying disability.  The program requirements for SSI are similar to those for Food Stamps or SNAP benefits.

Both SSDI and SSI are administered by the Social Security Administration (SSA) and follow the same definition of disability.  The SSA uses a 5-Step Sequential Evaluation to determine if someone's disability is severe enough to qualify for benefits.

Both programs use the same application form too, so everyone who applies for disability benefits also applies for SSI and vice versa.

Determining SSDI Eligibility

Who is considered "insured" under SSDI?

As stated above, to qualify for SSDI (to be "insured"), you need to have paid enough into Social Security and recently enough.

You can find out directly from the Social Security Administration (SSA) if you have worked long enough.

SSA determines this with “Work Credits”, aka “Social Security credits”, aka “Quarters of coverage” (QC), aka “Quarters”. They’re called “Quarters” because you can earn up to 4 per year.

Work Credits, or Quarters of Coverage, are based on earnings rather than hours worked.  The dollar amount you need to earn changes every year, just to make things extra complicated (actually because of inflation, but it seems more like a mean trick).  In 2022 for example, you earned 1 Work Credit for every $1,510 earned, up to 4 credits.  You can find this year's dollar amount on the SSA website.


Let’s break down how many Work Credits you need:

Determining Disability

Social Security defines disability with these 5 questions. Also known as the 5-Step Sequential Evaluation, SSA uses this to determine disability for both SSDI and SSI.


1 Social Security Administration, Disability Benefits | How You Qualify,

2 Social Security Administration, Retirement Benefits,