Social Security Disability Insurance, or SSDI, and Supplemental Security Income, or SSI, are programs administered by the Social Security Administration to provide benefits to people with disabilities. While it’s possible to qualify for both programs, they each have different eligibility requirements, funding sources, and benefit structures.
If you’re unsure whether you qualify for SSDI, SSI, or both, this guide will help you understand these programs and how to qualify for benefits.
What Are SSI and SSDI?
SSI is a needs-based program for those with minimal income and resources. It is funded through general tax revenues and is available to individuals with disabilities or those 65 or older.
SSDI is an insurance program that supports individuals who can no longer work full-time because of a disability. The program is funded through payroll taxes, including those paid by the applicant over the course of their career. You must have paid a sufficient amount into the program to be eligible for benefits.
Key Differences Between SSI and SSDI
Here’s a comparison of many important aspects of both Social Security disability programs:
- Eligibility: SSI eligibility is determined by your income and resources, while SSDI eligibility is based on your work history and the number of “credits” you’ve accrued throughout your career by paying payroll taxes into the system.
- Funding Source: SSI is financed by general tax revenues, while SSDI is directly funded through a dedicated Social Security payroll tax.
- Medical Eligibility: Both SSI and SSDI applicants must have a condition meeting the SSA’s disability criteria. You can also qualify for SSI without a disability if you are 65 or older.
- Work History: To qualify for SSDI, applicants must have accrued a certain number of work credits to qualify for benefits. Meanwhile, SSI does not have a work history requirement.
- Monthly Benefit Amount: SSI provides a lower maximum monthly benefit set by the federal government every year, up to $967 per month for individuals and $1,450 for couples in 2025. SSDI payments are based on the recipient’s past earnings and max out at $4,018 monthly in 2025 at full retirement age.
- Health Insurance: If you qualify for SSI, you also likely qualify for Medicaid, and some states may sign you up automatically. SSDI recipients are automatically enrolled in Medicare after a 24-month waiting period.
- Back Pay and Waiting Period: SSDI generally has a five-month waiting period before payments begin, but allows for back benefits of up to 12 months. SSI has no waiting period for benefits, and back pay is available for the time between applying and approval.
Qualifications: SSDI vs. SSI
Who Qualifies For SSI?
SSI is available for those with a monthly income of less than $2,020 and less than $2,000 in cash or assets. For couples, both limits increase to about $3,000.
Applicants must also either be 65 or older or have a qualifying disabling condition. The SSA defines a disabling condition as “a physical or mental impairment that substantially limits one or more major life activities.”
Those who qualify for SSI are also generally eligible for Medicaid, and some states will even automatically enroll applicants. However, some still require a separate application.
Who Qualifies for SSDI?
To be eligible for SSDI, one must work and pay into the Social Security system for years before becoming disabled. Individuals can earn up to four credits each year, and SSDI applicants are generally required to earn at least 20 work credits in the 10 years before the onset of their disability. However, those 30 or younger have more lenient work requirements.
SSDI also requires applicants to meet the SSA’s disability criteria, meaning they cannot perform “substantial gainful activity.” There are no caps on resources or assets for SSDI. However, individuals are not considered disabled if they can earn more than the substantial gainful activity limit, which is $2,700 for blind people and $1,620 for those with other disabilities in 2025.
Can You Receive Both SSI and SSDI?
It’s possible to be eligible for both SSI and SSDI, known as concurrent benefits. SSI can supplement a very low monthly SSDI benefit, but SSI benefits are reduced dollar-for-dollar for non-work income, including SSDI.
Adding SSDI while already receiving SSI may only marginally increase your monthly income. However, concurrently qualifying for both Medicare and Medicaid could give you faster and more comprehensive health care benefits.
Application Process: SSI vs. SSDI
The bulk of the application processes for SSI and SSDI are similar, but you’ll need to gather different documents depending on which program you’re applying for.
Records required to apply to either program include the following:
- Your birth certificate or other proof of birth, and proof of citizenship or immigration status if you were not born in the United States
- Discharge papers if you served in the military before 1968
- W2 forms, tax returns, or other documents establishing your work history or previous income
- Proof of any non-work income
- Medical records establishing your qualifying disability.
If you don’t have certain records in your possession, the SSA can request them from your medical providers.
While SSDI applicants need only prove their work history and current income, SSI applicants must also show that their resources and assets fall under the qualifying threshold. Additional required evidence can include bank statements, titles to any significant property, and proof of your current living arrangements.
How to Apply for SSI and SSDI
You can apply for SSDI and SSI online, by calling 1-800-772-1213, or by visiting a local SSA office. Once you’ve filed your application, it may take about six to eight months to receive a decision. If you’re denied, you must respond within 60 days to proceed through a multi-step appeals system, which can extend the application process by several months for each step.
Ensuring your initial application is accurate and contains all required documentation is key to avoiding delays and securing benefits as soon as possible. A knowledgeable Social Security disability lawyer can help you build a strong claim and make the application process as pain-free as possible.
How National Disability Alliance Can Help
If you’re confused about the difference between SSI and SSDI or need assistance with your application, the National Disability Alliance can help. Our team has former SSA professionals deeply experienced in providing compassionate legal support for individuals with disabilities like you, helping them file successful SSI, SSDI, and concurrent benefits claims.
We’re here to make the process faster and easier, and you won’t pay us anything unless we secure you the benefits you deserve. Contact us online or call 833-693-4722 today for a free consultation.
