Social Security Disability Insurance is calculated by indexing your lifetime earnings for wage growth, averaging your highest-earning years into a single monthly figure, and running that figure through a three-tier formula that pays 90%, 32%, and 15% across three earnings bands. For workers first eligible in 2026, the dollar cutoffs between those bands are $1,286 and $7,749, and the average disabled worker receives about $1,630 per month.1Social Security Administration. Benefit Formula Bend Points2Social Security Administration. 2026 Cost-of-Living Adjustment (COLA) Fact Sheet The amount you personally receive depends on your earnings history, the year your disability began, and a handful of adjustments that can raise or lower the base figure once it’s set.
Before any of this runs, you have to be insured. Most applicants need 20 work credits earned in the 10 years before disability onset; younger workers qualify with fewer.3eCFR. 20 CFR Part 404 Subpart B – Insured Status and Quarters of Coverage Once you’re insured, the calculation itself has two main steps.
Step One: Your Average Indexed Monthly Earnings
Everything starts with your Average Indexed Monthly Earnings (AIME), a single number that stands in for your entire work history.
Indexing Old Wages for Growth
A paycheck from 1995 isn’t directly comparable to one from 2020. The SSA scales up each year of your past earnings using the National Average Wage Index so older wages reflect economy-wide wage growth.4Social Security Administration. National Average Wage Index Wages from the two years before your disability onset, and the onset year itself, are counted at face value without indexing.
Dropping Your Weakest Years
After indexing, the SSA removes some of your lowest-earning years so a stretch of unemployment or low pay doesn’t drag your average down. For disability claims, the number of dropout years depends on how old you were when your disability began:5Social Security Administration. Annual Statistical Supplement – Glossary
- Age 26 or younger: 0 dropout years
- Age 27–31: 1 dropout year
- Age 32–36: 2 dropout years
- Age 37–41: 3 dropout years
- Age 42–46: 4 dropout years
- Age 47 or older: 5 dropout years
Time out of the workforce caring for a child under age 3 may add dropout years beyond the standard count. The SSA then totals your highest remaining indexed earnings and divides by the number of months in that period. That’s your AIME.6eCFR. 20 CFR 404.211 – Computing Your Average Indexed Monthly Earnings
You can pull your recorded earnings from a my Social Security account at ssa.gov. Check it. Reporting errors lower your benefit, and correcting them years later is much harder than fixing them now.
Step Two: Your Primary Insurance Amount
Your Primary Insurance Amount (PIA) is the monthly dollar figure the calculation produces before any adjustments. It comes from running your AIME through a three-tier progressive formula, with each tier replacing a smaller share of higher earnings.7Office of the Law Revision Counsel. 42 USC 415 – Computation of Primary Insurance Amount The cutoffs between tiers are called bend points, and the SSA sets new ones each year.
For workers first eligible for SSDI in 2026, the formula is:1Social Security Administration. Benefit Formula Bend Points
- 90% of the first $1,286 of your AIME
- 32% of your AIME between $1,286 and $7,749
- 15% of any AIME above $7,749
Add the three pieces together, round down to the nearest ten cents, and that’s your PIA.7Office of the Law Revision Counsel. 42 USC 415 – Computation of Primary Insurance Amount Because the top tier pays only 15 cents on the dollar, workers with modest lifetime earnings see a much larger share of their wages replaced than higher earners do.
A Worked Example
Say your AIME comes out to $4,500. Using the 2026 bend points:
- 90% × $1,286 = $1,157.40
- 32% × ($4,500 − $1,286) = 32% × $3,214 = $1,028.48
- Nothing above $7,749
The sum is $2,185.88. Rounded down, the PIA is $2,185.80 per month.
Adjustments That Change the Check You Actually Receive
The PIA is the starting point. Several rules can push your monthly payment up or down from there.
Annual Cost-of-Living Adjustments
Once your PIA is set, it grows each year with inflation. The 2026 COLA is 2.8%, applied to existing recipients’ checks starting in January.2Social Security Administration. 2026 Cost-of-Living Adjustment (COLA) Fact Sheet The adjustment is automatic and continues for as long as you receive benefits.
Workers’ Compensation and Other Public Disability Offsets
If you also collect workers’ compensation or certain other public disability payments, federal law caps the combined total (including any family benefits paid on your record) at 80% of your “average current earnings,” a figure taken from the highest of three calculations based on your pre-disability income.8Office of the Law Revision Counsel. 42 USC 424a – Reduction of Disability Benefits Anything over the cap is subtracted from your SSDI check.
If your average current earnings were $5,000 per month, the 80% cap is $4,000. An SSDI benefit of $2,000 plus workers’ compensation of $2,500 totals $4,500, which is $500 over the cap. The SSA reduces the SSDI payment by that $500, bringing it to $1,500.
Some income doesn’t trigger the offset at all. VA disability benefits, need-based assistance, and benefits tied to work covered by a state Social Security agreement are excluded.8Office of the Law Revision Counsel. 42 USC 424a – Reduction of Disability Benefits
The Family Maximum
When your spouse or children draw benefits on your record, total household payments are capped by a family maximum. For disability, the maximum is 85% of your AIME, but it can never fall below your PIA or exceed 150% of your PIA.9Social Security Administration. Maximum Benefit for a Disabled-Worker Family If total family benefits exceed the cap, only the dependents’ payments are cut, proportionally, until the household total fits within the limit. Your own check is never reduced to satisfy the family maximum.10eCFR. 20 CFR 404.403 – Reduction Where Total Monthly Benefits Exceed Maximum Family Benefits Payable
Things That Affect the Payment but Not the Calculation
A few rules shape what lands in your bank account without changing the underlying PIA.
The five-month waiting period. Your first payment covers the sixth full month after your established disability onset date. Back pay can also reach up to 12 months before your application date if you were disabled and eligible during that window.11Office of the Law Revision Counsel. 42 USC 423 – Disability Insurance Benefit Payments Applicants diagnosed with ALS skip the waiting period entirely.12Social Security Administration. What You Need to Know When You Get Social Security Disability Benefits
Federal income tax. If your combined income (adjusted gross income, plus nontaxable interest, plus half your annual benefits) is above $25,000 single or $32,000 married filing jointly, up to 50% of your benefits become taxable; above $34,000 or $44,000, up to 85%.13Office of the Law Revision Counsel. 26 USC 86 – Social Security and Tier 1 Railroad Retirement Benefits These thresholds are fixed in statute and never adjust for inflation. Married filing separately while living with your spouse drops the base to zero, making benefits taxable at any income level.
Medicare Part B premium. After a 24-month qualifying period, you’re enrolled in Medicare.14Social Security Administration. Medicare Information The 2026 standard Part B premium is $202.90, deducted directly from your monthly SSDI payment.15Centers for Medicare & Medicaid Services. 2026 Medicare Parts A and B Premiums and Deductibles Factor that deduction into any budgeting you do around your gross benefit figure.