How much will I actually get from SSI vs. SSDI?

Here's how the concurrent math actually works in 2026. Say your SSDI is $700/month. SSI counts SSDI as unearned income. Apply the $20 General Income Disregard: $700 - $20 = $680 countable. SSI top-up = $994 (FBR) - $680 = $314.

Total monthly cash: $700 SSDI + $314 SSI = $1,014 — which is $20 above the FBR. That $20 effective bump is the GID at work. If your SSDI is at or above $1,014 (FBR + $20), no SSI cash. Below that, SSI fills the gap.

If your SSDI exceeds $1,014/month (the 2026 FBR plus the $20 GID), you won't see any SSI cash. SSDI alone applies, and SSI doesn't help.

But don't stop there. If you're approaching Medicare age (24 months after SSDI entitlement), Extra Help / LIS may still apply based on your income and resources independent of SSI. The thresholds are different. Apply separately when the time comes.

Earned income gets a much better deal than unearned. The exclusion: first $65 of monthly earned income is excluded, then half of the remainder.

Example: you earn $300 in a month. ($300 - $65) / 2 = $117.50 countable. So a $300 paycheck only reduces your SSI by $117.50. If you also have unearned income, the $20 GID applies first to that (or to the earned income if no unearned).

SSDI back pay usually arrives as a single lump-sum deposit within about 60 days of approval. It can cover up to 12 months retroactive to your application (minus the 5-month waiting period from disability onset).

SSI back pay only goes back to your application date — no retroactivity. And if it exceeds 3 times the FBR ($2,982 in 2026), it's paid in 3 installments roughly 6 months apart.

Child support paid to a child receiving SSI gets a special break. One-third of the support amount is excluded outright. The remaining two-thirds is unearned income to the child, which then gets the $20 GID.

Example: $300 monthly child support to a child on SSI. $100 (one-third) excluded. $200 counted as unearned. After $20 GID: $180 countable. SSI reduced by $180.

Two extra exclusions can reduce countable earned income further: Impairment-Related Work Expenses (IRWE) and Plans to Achieve Self-Support (PASS).

IRWE: out-of-pocket costs for items/services you need because of your disability to work (specialized transportation, attendant care, certain medications). These are subtracted from earned income before the standard $65 + half formula.

PASS: a written plan, approved by SSA, to set aside income or resources toward a vocational goal. Money set aside in an approved PASS doesn't count as income or resources for SSI.

If you're helping a parent, spouse, or adult child figure out the SSI/SSDI math, the calculations are the same regardless of who runs them. What's different is the paperwork at filing.

If you're a representative payee, you'll fill out Form SSA-11. Power of attorney works for some banking-side tasks but doesn't satisfy SSA — SSA has its own rep-payee process. For an adult child with a disability that started before age 22, also look into Disabled Adult Child (DAC) benefits on a parent's record — a separate calculation entirely.

If your situation isn't on this page, the safest move is to call SSA at 1-800-772-1213 or go in to a local office with whatever paperwork you have. The math is mostly mechanical — SSA will tell you what your numbers look like once they have the income and resource picture.

Before the appointment, two things help: pull a my Social Security earnings summary (so you know your SSDI PIA estimate) and write down every income source plus its frequency. The more concrete you are, the cleaner the answer.