The core difference: who you are and how long you've worked

Social Security Disability Insurance (SSDI) and Supplemental Security Income (SSI) are two separate programs that both pay monthly benefits to people who cannot work due to disability. The main difference is how you become may be able to access. SSDI is based on your own work history and the taxes you've paid into Social Security. SSI is based on financial need — it doesn't matter whether you've worked before.

SSDI requires that you or your parent (if you're applying as a child) have worked long enough and paid enough Social Security taxes to build up a work record. SSI has no work requirement at all. Instead, it looks at your income and assets right now. If you have very little money and own very few things, you may be may be able to access for SSI even if you've never had a job.

Both programs use the same definition of disability — you must have a medical condition that prevents you from working and is expected to last at least 12 months or result in death. But the path to proving you're disabled, and the amount you receive each month, can be quite different.

Key Takeaways

  • SSDI is for people with a work history who have paid Social Security taxes; SSI is for people with limited income and assets regardless of work history.
  • SSDI benefit amounts are based on your past earnings; SSI benefit amounts are set by the federal government and vary by state.
  • You can receive both SSDI and SSI at the same time if your SSDI payment is very low.
  • SSDI allows you to earn more money while receiving benefits; SSI has stricter limits on how much you can earn.
  • Family members can receive benefits on your SSDI record, but not on your SSI record.

How work history affects which program you can receive

To receive SSDI, you need what Social Security calls "insured status." This means you've worked in jobs where you paid Social Security taxes, and you've accumulated enough work credits. The number of credits you need depends on your age when you become disabled. A younger person typically needs fewer credits than someone who becomes disabled later in life. You can check your work record and credits by creating an account on ssa.gov.

SSI has no work requirement. You don't need any work credits or employment history. This makes SSI the program available to people who have never worked, including children and young adults who became disabled before they could enter the workforce. It's also available to older adults who didn't work long enough to may have access to for SSDI.

If you have some work history but not enough to may have access to for SSDI, you may still be able to receive SSI. The two programs can overlap — your work history doesn't disqualify you from SSI if you meet the financial need test.

How monthly benefit amounts are calculated

SSDI payments are based on your average lifetime earnings. The higher your earnings were during your working years, the higher your SSDI benefit will be. Social Security calculates this by looking at your 35 highest-earning years and averaging them. This means two people with the same disability can receive very different SSDI amounts depending on how much they earned.

SSI payments are different. The federal government sets a maximum monthly amount, called the Federal Benefit Rate, which changes each year. In 2024, this amount varies, but most states use the federal rate as their baseline. Some states add extra money on top of the federal amount. Unlike SSDI, your past earnings don't affect your SSI payment — only your current income and assets do.

Because SSDI is based on your work record, you can receive a very high SSDI payment if you earned a lot. SSI payments are typically lower because they're designed as a safety net for people with very limited resources, not as a replacement for your full past income.

Income and asset limits: how they affect your benefits

SSI has strict limits on how much money you can have. You cannot own more than $2,000 in countable assets (or $3,000 if you're married and both applying). Your home and one vehicle don't count toward this limit, but savings accounts, stocks, and other property do. If you exceed the asset limit, you lose SSI entirely.

SSDI has no asset limit. You can own a house, multiple cars, and have savings in the bank without affecting your SSDI payment. This is a major difference for people who have built up some wealth or who inherit money.

Both programs limit how much earned income you can have while still receiving benefits, but the limits are different. SSDI allows you to earn more before your benefits are reduced. SSI has lower earning limits and reduces your payment more quickly as you earn money. If you're working or thinking about working while receiving benefits, the program you're on makes a real difference in how much you can earn.

Family benefits: who else can receive money on your record

If you receive SSDI, your spouse, ex-spouse, and children may be able to receive benefits based on your work record. A spouse can receive up to 50 percent of your benefit amount, and each child can receive up to 75 percent. There's a family maximum — the total amount all family members can receive together — but multiple people can draw from your single work record.

SSI does not pay family members based on your record. Only you receive the benefit. Your spouse's or children's income and assets are counted when determining whether you're may be able to access for SSI, but they cannot receive their own SSI payments based on your application.

This is an important distinction if you're supporting a family. SSDI can provide income for multiple household members, while SSI is an individual benefit only.

Work incentives and how much you can earn

Both programs want to encourage you to work if you're able to, so both have rules that let you earn some money without losing all your benefits. But the rules are more generous under SSDI.

SSDI has a "trial work period" that lasts nine months. During this time, you can earn any amount and still receive your full SSDI benefit. After the trial work period ends, your benefits are reduced if you earn above a certain amount (called substantial gainful activity). You have a 36-month window to use your trial work period, and it doesn't have to be consecutive months.

SSI allows you to earn $65 per month before your benefit is reduced, and then your benefit is reduced by 50 cents for every dollar you earn above that. This means earning even a small amount of money significantly reduces your SSI payment. SSI also has an "impairment-related work expense" deduction that lets you exclude certain work-related costs, but the basic earning limit is much lower than SSDI.

Medical review and continuing may be able to access

Both SSDI and SSI require you to prove you're still disabled. Social Security will review your case periodically to make sure you still meet the disability definition. How often this happens depends on whether your condition is expected to improve. If Social Security thinks your condition might improve, they review you more frequently. If your condition is not expected to improve, reviews happen less often.

The review process is the same for both programs — you'll receive a letter asking you to provide updated medical evidence. If you don't respond or if Social Security decides you're no longer disabled, your benefits can stop. You have the right to appeal any decision to stop your benefits.

Frequently Asked Questions

Can I receive both SSDI and SSI at the same time?

Yes. If your SSDI payment is very low, you may receive both programs together. Social Security will pay your SSDI first, and then SSI will make up the difference if you meet SSI's income and asset limits. This is called "concurrent benefits," and it's common for people with low work histories.

If I'm on SSI, will getting married affect my benefits?

Yes. When you marry, your spouse's income and assets are counted toward your SSI may be able to access. This can reduce or eliminate your SSI payment. SSDI is not affected by marriage in the same way — your spouse's income doesn't count against you, though your spouse may be able to receive their own benefit based on your work record.

What happens to my benefits if I go back to work?

It depends which program you're on. SSDI gives you a nine-month trial work period where you can earn any amount. SSI reduces your payment by 50 cents for every dollar you earn above $65 per month. Both programs have work incentives, but SSDI's are more generous if you want to test whether you can work.

Can I switch from SSI to SSDI if I work enough to build up credits?

Yes. If you're receiving SSI and you work enough to build up the work credits needed for SSDI, you can transition to SSDI. Your SSI will stop when your SSDI begins, but you may receive both for a short time if your SSDI payment is low. Social Security will handle this transition for you.

Do I have to report my income to Social Security every month?

For SSI, yes — you're required to report changes in your income and resources. For SSDI, you only need to report if you're earning money and want to use the work incentives. Social Security will tell you what you need to report and how often. Failing to report can result in overpayments that you'll have to repay.