If a disability keeps you from working, Social Security may be able to help. But there are two different programs with very similar names, and mixing them up is one of the most common sources of confusion. Here’s the difference in plain English.
SSDI: based on your work history
Social Security Disability Insurance (SSDI) is for people who worked long enough, and recently enough, to earn Social Security credits. Your monthly benefit is based on your past earnings. After a waiting period, SSDI recipients usually become eligible for Medicare.
SSI: based on financial need
Supplemental Security Income (SSI) is for people with very low income and few resources who are disabled, blind, or 65 or older. You don’t need a work history. In most states, people who receive SSI can also get Medicaid.
Quick comparison
- SSDI requires work credits. SSI does not.
- SSDI amount depends on past earnings. SSI pays a set federal amount, which some states add to.
- SSDI usually leads to Medicare. SSI usually comes with Medicaid.
- Some people qualify for both at the same time.
How Social Security defines disability
For adults, Social Security generally looks at whether you have a medical condition that prevents you from doing substantial work and that is expected to last at least a year or result in death. It’s a strict standard, and many first applications are denied.
How to apply
- Apply online at SSA.gov, by phone, or at your local Social Security office.
- Gather medical records, names of doctors and clinics, medications, and your work history.
- Answer all requests from Social Security quickly.
- If denied, you have the right to appeal. Many people win on appeal, sometimes with help from a lawyer or advocate.
A real-life example
Robert worked in construction for twenty years until a back injury made it impossible to lift heavy materials. He applied for SSDI and was denied the first time. With help from a legal aid advocate, he gathered more detailed medical records and statements from his doctors and appealed.
His appeal was approved. Because his application date was used, he also received back payments for the months he had been waiting.
Tips from people who have been through it
- Apply as soon as you’re unable to work. Don’t wait.
- Keep a list of every doctor, clinic, and hospital you’ve visited.
- Never miss an appeal deadline.
- Ask local legal aid or disability advocacy groups for free help.
Frequently asked questions
How long does it take to get approved?
It often takes several months, and longer if you appeal. Apply as soon as you can.
Can I work while on disability?
There are rules that allow limited work, and work incentive programs like Ticket to Work. Report all work to Social Security.
Do I need a lawyer?
Not to apply, but many people get help for appeals. Disability lawyers usually only get paid if you win.
Related guides
- Medicaid Eligibility and How to Apply in Your State
- Lifeline Program: Discounted Phone and Internet Service
- Housing Help for Seniors: Affordable Options After 62
Official resources
This guide is for general information only. US Assistance Guide is an independent website and is not affiliated with, endorsed by, or connected to any government agency. Program rules, income limits, and benefit amounts change often and vary by state, so always confirm details with the official agency before you apply.