How to Calculate Your AIME for SSDI Benefits

Your SSDI payment isn't pulled from thin air. It's the result of a formula — and at the center of that formula is a number called your Average Indexed Monthly Earnings, or AIME. Understanding how the SSA calculates your AIME helps explain why two people with similar disabilities can receive very different monthly benefit amounts.

What Is AIME and Why Does It Matter?

AIME is the foundation of your SSDI benefit calculation. The Social Security Administration uses it to measure your average monthly earnings over your working life, adjusted for wage growth over time. From your AIME, the SSA then derives your Primary Insurance Amount (PIA) — the actual dollar figure you receive each month.

In short: higher AIME = higher PIA = higher monthly benefit. But the relationship isn't dollar-for-dollar. The formula is deliberately weighted to replace a larger share of earnings for lower-wage workers.

Step 1 — Identify Your Earnings Record

The SSA starts with your actual reported earnings from every year you worked and paid into Social Security. These wages are pulled from your Social Security earnings record, which you can review at ssa.gov using a My Social Security account.

Only earnings on which you paid FICA taxes count. Self-employment income counts if Social Security taxes were paid on it. Income above the annual taxable maximum (which adjusts each year) is excluded from the record.

Step 2 — Index Your Earnings to Account for Wage Growth 📊

Raw earnings from decades past would be misleadingly low compared to today's wages. To correct for this, the SSA indexes each year's earnings using the Average Wage Index (AWI).

Here's how that works:

• The SSA picks an indexing year — typically the second year before you became disabled or turned 62, whichever comes first
• Each year of earnings before the indexing year is multiplied by a ratio: the AWI in your indexing year ÷ the AWI in the year you earned those wages
• Earnings from the indexing year and later are counted at their actual nominal value — no adjustment

This means wages you earned early in your career get scaled upward to reflect what they'd be worth in today's economy. A $20,000 salary from 1990 becomes a significantly larger indexed figure when measured against current wage levels.

Step 3 — Select the Highest 35 Years

Once all eligible years are indexed, the SSA selects your 35 highest-earning years. These are the years that will count toward your AIME.

If you have fewer than 35 years of covered earnings, zeroes are added to fill the remaining slots. Those zeroes drag the average down — which is why a shorter work history directly reduces your AIME and, ultimately, your monthly benefit.

Step 4 — Divide by 420

Once the SSA has totaled your 35 highest indexed annual earnings, it divides that sum by 420 — the number of months in 35 years. The result is your AIME.

The formula looks like this:

AIME = Sum of top 35 indexed annual earnings ÷ 420

For example: If your top 35 indexed years add up to $1,680,000, your AIME would be $4,000 per month.

Step 5 — Convert AIME to Your Benefit Using Bend Points

Your AIME feeds into the PIA formula, which uses fixed percentages applied to income brackets called bend points. These bend points adjust annually with wage growth.

The structure (using illustrative, not current-year figures) works like this:

• 90% of the first portion of AIME (up to the first bend point)
• 32% of AIME between the first and second bend points
• 15% of any AIME above the second bend point

This tiered structure means lower earners see a proportionally higher replacement rate. A worker with a $1,200 AIME may have nearly 80% of their pre-disability earnings replaced. A worker with a $6,000 AIME will see a much smaller percentage replaced — even though their raw benefit amount is larger.

Bend point thresholds change every year, so the exact numbers depend on when your disability began.

What Changes Your AIME — and What Doesn't

Several factors shape where your AIME lands:

• Length of work history — More years of substantial earnings reduces the zero-year drag
• Earnings level — Higher wages in covered employment push indexed totals up
• Age at disability onset — An earlier onset date means fewer working years before calculation, potentially more zeroes
• Type of income — Only wages subject to Social Security taxes count; investment income, pensions from non-covered jobs, and certain government earnings do not

What doesn't change your AIME: your medical diagnosis, the severity of your condition, or how long your disability has lasted. The AIME is purely a wage-history calculation.

Why the Same Diagnosis Can Produce Very Different Benefits 💡

Two people both approved for SSDI with identical conditions can receive drastically different monthly payments. One person worked 30 years at above-average wages. Another worked part-time for 15 years. Their AIMEs — and therefore their PIAs — will reflect those differences entirely.

The SSA publishes average SSDI benefit figures annually (amounts adjust with cost-of-living adjustments, or COLAs), but those averages mask an enormous range of individual outcomes driven entirely by earnings history.

Your own AIME depends on the specific contours of your work record — the years you worked, what you earned, which years were highest, and how many gaps exist. That's the piece no general explanation can fill in for you.