The Basic Formula: Your Earnings History Determines Your Amount

Social Security calculates your SSDI payment using a formula based on your Primary Insurance Amount (PIA), which comes from your earnings record over your entire working life. The Social Security Administration (SSA) does not look at your current need or how much money you have in the bank. Instead, they look at what you earned in covered employment — jobs where you paid Social Security taxes — and convert that into a monthly benefit amount.

The calculation starts with your average indexed monthly earnings (AIME). SSA takes your highest 35 years of earnings, adjusts them for inflation using an index, and divides by 420 months to get a monthly average. Then they explore a bend point formula that replaces a higher percentage of lower earnings and a lower percentage of higher earnings. This means someone who earned less during their working years gets a larger percentage of their past earnings back as a benefit.

Your actual SSDI payment is your PIA, unless you are under full retirement age and still working — in which case SSA may reduce your payment if you earn above a certain amount. Once you reach full retirement age, your earnings no longer affect your SSDI payment.

Key Takeaways

  • Your SSDI payment is based on your earnings record, not your current financial need or savings.
  • Social Security uses your 35 highest-earning years and adjusts them for inflation to calculate your average monthly earnings.
  • The bend point formula gives you a larger percentage of your lower earnings and a smaller percentage of your higher earnings.
  • If you are under full retirement age and working, SSA may reduce your payment if you earn more than the annual limit, which changes each year.
  • Your payment amount is set when you are first approved and increases each year with the Cost-of-Living Adjustment (COLA).

How SSA Gathers and Indexes Your Earnings

Social Security has a record of your earnings for every year you worked in a job covered by Social Security. You can see this record by creating a my Social Security account online at ssa.gov. SSA uses W-2 forms and self-employment tax returns to build this history.

Before calculating your average, SSA indexes your earnings to account for wage growth over time. They do not straightforward add up your raw earnings from 1985 and 2020 — that would unfairly penalize people who worked decades ago. Instead, they multiply your earnings in each year by an index factor based on the national average wage for that year. This brings all your past earnings into a common scale, as if they had all happened in the same economic period.

SSA uses the year you turn 60 as the indexing year for most people. If you became disabled before age 60, they use the year you became disabled. They then select your 35 highest indexed years and add them up. If you have fewer than 35 years of earnings, they count zeros for the missing years, which lowers your average and your payment.

The Bend Point Formula and Why Your Payment Replaces Different Percentages

Once SSA has your average indexed monthly earnings (AIME), they explore the bend point formula. This formula has two or three "bend points" — dollar amounts that change each year. In 2024, the bend points are $1,174 and $7,078, but these amounts change annually based on wage growth.

Here is how it works: SSA replaces 90 percent of your AIME up to the first bend point, 32 percent of your AIME between the first and second bend points, and 15 percent of your AIME above the second bend point. This structure means a worker with a low lifetime average gets back a much larger share of their past earnings, while a worker with a high lifetime average gets back a smaller share.

Example: If your AIME is $2,000, SSA would calculate (90% × $1,174) + (32% × ($2,000 − $1,174)) + (15% × $0) = $1,056.60 + $264.32 = $1,320.92. That is your Primary Insurance Amount before any reductions. The exact bend points for your year of approval are what matter, not the 2024 figures.

Work Incentives and Earnings Limits Before Full Retirement Age

If you are under your full retirement age and you work, SSA will reduce your SSDI payment if your earnings exceed an annual limit. In 2024, that limit is $23,400, but it changes each year. SSA subtracts $1 from your benefit for every $2 you earn above the limit.

The month you reach full retirement age, the earnings limit goes away entirely. After that month, you can earn any amount without a reduction to your SSDI payment. Your full retirement age depends on your birth year: it ranges from 66 to 67 for people born between 1943 and 1960, and is 67 for people born in 1960 or later.

There is also a trial work period that lets you test your ability to work without losing your SSDI status. During this nine-month period, you can earn any amount and keep your full SSDI payment. After the trial work period ends, the earnings limit applies for the next 36 months. If you stay under the limit during those 36 months, your SSDI ends. If you go over the limit, you enter an extended period of may be able to access where you can still receive benefits in months you earn under the limit.

Cost-of-Living Adjustments and Annual Payment Changes

Your SSDI payment does not stay the same forever. Each year, SSA increases payments by the Cost-of-Living Adjustment (COLA), which is tied to inflation. The COLA is announced in October and takes effect the following January. In recent years, COLA increases have ranged from 0 percent (in 2010 and 2011) to 8.7 percent (in 2023), depending on inflation.

You do not have to do anything to receive the COLA increase — it happens automatically. SSA sends a notice in December showing your new payment amount starting in January. If you have questions about the increase, you can call SSA at 1-800-772-1213 or check your my Social Security account online.

How Family Members' Payments Are Calculated

If you are approved for SSDI, certain family members may also receive payments based on your earnings record. These include your spouse (at any age if caring for a child under 16, or at age 62 or older), your unmarried children under 19 (or up to 22 if in high school full-time), and your adult children if they were disabled before age 22.

Family members do not get their own separate calculation. Instead, SSA calculates a family maximum, which is usually 150 to 180 percent of your Primary Insurance Amount. The total paid to all family members combined cannot exceed this maximum. If multiple family members are receiving benefits, SSA divides the family maximum among them. This means your payment may be reduced if other family members are also on your record.

For example, if your PIA is $1,500 and the family maximum is 180 percent, the total paid to you and all family members is $2,700. If your spouse and two children are also receiving benefits, that $2,700 is split among all four of you.

What Happens to Your Payment If You Receive Other Benefits

SSDI payments are not reduced if you receive unemployment benefits, workers' compensation, or other state or local benefits. However, if you receive a pension from work where you did not pay Social Security taxes — such as some government jobs — SSA may reduce your SSDI payment under the Government Pension Offset or Windfall Elimination Provision. These rules are complex and depend on your specific work history.

If you are also receiving Supplemental Security Income (SSI), your SSDI payment is counted as income and may reduce your SSI amount. SSA coordinates these two programs so you do not receive duplicate payments for the same month.

Frequently Asked Questions

Can I see how much my SSDI payment will be before I am approved?

You can get an estimate by creating a my Social Security account at ssa.gov and viewing your earnings record. The site shows an estimated benefit amount based on your current earnings history. This estimate changes as you earn more, and it is not a may provide of what you will actually receive. Your final payment amount is determined only after SSA approves your claim and calculates your PIA using the bend points in effect that year.

Why is my SSDI payment different from my spouse's or child's payment?

Family members receive a percentage of your Primary Insurance Amount, not their own separate calculation. A spouse typically gets 50 percent of your PIA, and children get 75 percent each. If the total for all family members exceeds the family maximum, each payment is reduced proportionally. Your own payment is never reduced because of family members receiving benefits.

What if I worked for a government employer and did not pay Social Security taxes?

If you have a pension from government work where you did not pay Social Security taxes, the Windfall Elimination Provision (WEP) may reduce your SSDI payment. WEP changes how your bend points are calculated, usually lowering your benefit. The reduction is capped at 50 percent of your government pension amount. You can contact SSA to learn whether WEP applies to your specific work history.

Does my SSDI payment increase if I work during my trial work period?

No. Your SSDI payment stays the same during your trial work period, regardless of how much you earn. The trial work period is designed to let you test your ability to work without losing benefits. After the trial work period ends, the earnings limit applies, and SSA will reduce your payment if you earn above the annual limit.

When does my COLA increase take effect?

The COLA increase takes effect in January of each year. SSA announces the percentage increase in October. You will receive a notice in December showing your new payment amount starting in January. The increase is automatic — you do not need to do anything or contact SSA to receive it.