Social Security Glossary & Acronyms

This glossary covers every term and acronym you’ll encounter on the rest of the site, in your Social Security statement, in SSA correspondence, and in the benefit-eligibility decisions described across the video library.

A

AIME — Average Indexed Monthly Earnings {#aime}

The 35-year average of your wage-indexed earnings, the input to the PIA formula. Each year of covered earnings is “indexed up” to the wage level of the year you turn 60, then the top 35 years are averaged. Years where you didn’t work or worked outside Social Security count as zeros and pull the average down. Source: 42 U.S.C. § 415(b).

ARF — Adjusted Reduction Factor {#arf}

The recalculation SSA performs when you reach Full Retirement Age after having benefits withheld under the earnings test. The withheld months are credited back as if you had claimed later, increasing your monthly benefit going forward.

C

COLA — Cost-of-Living Adjustment {#cola}

The annual benefit increase computed from the year-over-year change in CPI-W during Q3. Announced each October for the following year. The 2026 COLA is 2.5%.

CPI-W {#cpi-w}

Consumer Price Index for Urban Wage Earners and Clerical Workers — the inflation gauge SSA uses for COLA. Critics argue CPI-E (for the elderly) would more accurately reflect retiree costs, but Congress has not adopted it.

D

DRC — Delayed Retirement Credit {#drc}

The 2/3 of 1% per month (8% per year) bonus added to your benefit for every month you delay claiming past Full Retirement Age, up to age 70. There is no DRC past 70 — claiming at 71 leaves money on the table.

DAC — Disabled Adult Child {#dac}

A benefit for an unmarried adult child of a deceased, retired, or disabled worker if the child became disabled before age 22. The DAC benefit is 50% of the parent’s PIA (75% if the parent is deceased).

E

Earnings Test {#earnings-test}

Pre-FRA earnings limit that triggers benefit withholding when you work while collecting. 2026 limits: $23,400 (under FRA all year, $1 withheld per $2 over) and $62,160 (year you reach FRA, $1 per $3 over, only earnings before FRA-month count). See the Earnings Test Calculator.

F

FICA — Federal Insurance Contributions Act {#fica}

The payroll tax that funds Social Security (6.2%) and Medicare (1.45%) — both matched by your employer for a total of 15.3%. Self-employed workers pay both halves themselves, as SECA tax. The Social Security portion only applies to wages up to the annual wage base ($176,100 in 2026).

FRA — Full Retirement Age {#fra}

The age at which you become entitled to 100% of your PIA. Ranges from 65 to 67 depending on birth year. See the Full Retirement Age Calculator.

G

GPO — Government Pension Offset {#gpo}

Pre-2024 rule that reduced spousal/survivor benefits for people who also received a pension from non-Social Security-covered government work. Repealed by the Social Security Fairness Act (P.L. 118-273), signed January 2025. Affected workers receiving back pay through 2025 and 2026.

I

IRMAA — Income-Related Monthly Adjustment Amount {#irmaa}

Surcharges on Medicare Part B and Part D premiums for higher-income beneficiaries. Five income brackets above the base; thresholds start at $103,000 single / $206,000 MFJ for 2026 (based on your 2024 tax return). Often catches people the year they convert traditional IRA money to Roth.

M

MAGI — Modified Adjusted Gross Income {#magi}

Your AGI plus tax-exempt interest. The basis for IRMAA bracket determination and several other Social Security and Medicare calculations.

my Social Security {#mysocialsecurity}

The free SSA online account at ssa.gov where you can check your earnings record, see your projected benefits at every claiming age, request your statement, apply for benefits, and lock down your record against identity theft. Everyone with a Social Security number should create an account.

O

OASDI — Old-Age, Survivors, and Disability Insurance {#oasdi}

The formal name of the Social Security program covering retirement, survivor, and disability benefits. The “Social Security” you hear about colloquially is the OASI portion (retirement and survivors); SSDI is the DI portion.

P

PIA — Primary Insurance Amount {#pia}

The monthly benefit you would receive if you claimed exactly at your Full Retirement Age. The output of the PIA formula applied to your AIME. Everything else (early reduction, delayed credits, spousal benefits, survivor benefits) is computed as a percentage of PIA.

POMS — Program Operations Manual System {#poms}

SSA’s official manual for adjudicating claims. The authoritative source for how the program rules are applied in practice. Public-facing sections are useful when you want to know exactly how SSA will treat your situation.

Q

QC — Quarter of Coverage (Credit) {#qc}

The unit of work credit toward Social Security eligibility. Earning $1,810 in covered wages in 2026 = 1 credit. Up to 4 credits per year. 40 credits required for retirement; fewer for disability and survivor benefits when the worker is young.

S

SECA — Self-Employment Contributions Act {#seca}

The self-employed equivalent of FICA — 12.4% Social Security + 2.9% Medicare = 15.3% on net self-employment earnings, paid as part of your federal tax return (Schedule SE). Half of SECA tax is deductible above-the-line.

SGA — Substantial Gainful Activity {#sga}

The earnings level above which SSDI benefits are generally not available. 2026 limits: $1,620/month non-blind, $2,700/month blind. Trial Work Period rules allow brief earnings above SGA without losing benefits.

SSA — Social Security Administration {#ssa}

The independent federal agency that administers the OASDI and SSI programs. Headquartered in Woodlawn, Maryland; over 1,200 field offices nationwide.

SSDI — Social Security Disability Insurance {#ssdi}

The disability portion of OASDI, funded by FICA payroll taxes and available to workers with sufficient credits who can no longer perform substantial gainful activity. Different rules from SSI; some people qualify for both (“dual eligibility” or “concurrent benefits”).

SSI — Supplemental Security Income {#ssi}

The needs-based program for low-income aged, blind, and disabled people — funded by general Treasury revenue, not FICA. Strict resource limits ($2,000 individual / $3,000 couple, unchanged since 1989). 2026 maximum federal payment is $967/month for an individual.

Social Security Fairness Act (P.L. 118-273) {#fairness-act}

Federal law signed January 5, 2025 that repealed both WEP and GPO, restoring full Social Security benefits to about 3 million public-sector retirees (teachers, firefighters, police, federal employees in the CSRS system). SSA processed retroactive back-payments through 2025 and 2026.

T

Trust Fund — OASI and DI Trust Funds {#trust-fund}

The combined account that holds incoming FICA receipts plus interest on Treasury securities. Net program payouts come from the trust fund. The “depletion date” you see in headlines is when the trust fund balance is projected to reach zero — at which point ongoing FICA receipts would still cover roughly 80% of scheduled benefits unless Congress acts.

W

Wage Base — Social Security Taxable Maximum {#wage-base}

The annual earnings ceiling above which the 6.2% Social Security FICA tax does not apply. $176,100 for 2026. Adjusts each year by the National Average Wage Index. (The 1.45% Medicare portion has no wage base.)

WEP — Windfall Elimination Provision {#wep}

Pre-2024 rule that reduced your own retirement benefit if you also received a pension from non-Social Security-covered work. Repealed by the Social Security Fairness Act, signed January 2025.