It May Concern

How we calculate

Updated · By It May Concern · How we check figures

Every estimate on this site comes from public rules and official figures. Here is exactly what the calculator does, and where it can differ from your official amount.

The figures

Each number is stored once, with its source, its status and the date we last checked it. Every page reads from that one list, so a change shows up everywhere at once. The full list is on the Sources page.

  • Official published by SSA, CMS or another government source
  • Calculated from official data worked out from official data with the formula set by law, before the agency announces it
  • Projection a government projection, such as the Medicare trustees’ premium forecast
  • Estimate a forecast from a named outside source, or our own arithmetic on official figures
  • Not announced yet no reliable figure exists yet

The Social Security steps

  1. Before-deductions amount. If you enter your deposit instead, we add back the 2026 Part B premium (and any income-related amount and other deductions you entered) to get it.
  2. COLA. We multiply by 1 + the COLA and round down to the whole dollar, as SSA does for the monthly benefit.
  3. Part B premium. If Part B comes out of your check, we subtract the 2027 standard premium. For income-related tiers we scale the official 2026 tier amount by the change in the standard premium, until CMS publishes 2027 amounts.
  4. Hold harmless. If your premium was taken from Social Security in 2026 and you’re in the standard tier, your premium increase is capped at your raise in dollars.
  5. Part D income-related amount. We use the 2026 amount for your tier until 2027 amounts are published.
  6. Other deductions you enter are assumed to stay the same.
  7. Payment date. From SSA’s rules: 2nd, 3rd or 4th Wednesday by birthday, the 3rd for people who started before May 1997 or get SSI too, the 1st for SSI, moved to the business day before any weekend or federal holiday.

The SSI steps

  1. We raise the 2026 federal SSI maximum by the COLA and round down to the dollar.
  2. Your SSI goes up by the same dollar amount as the maximum.
  3. If you also get Social Security, your SSI goes down by your Social Security raise, because SSI counts it as income.
  4. State supplements aren’t included.

Where your official amount can differ

  • SSA applies the COLA to your primary insurance amount and other figures in your record, with rounding at several steps. Our estimate can be off by a dollar or two.
  • Medicare Advantage and Part D plan premiums change every January, and we can’t know yours.
  • If you’re working, owe an overpayment, have a garnishment or are affected by other adjustments, your deposit will differ.

Testing

The calculator’s math is checked by automated tests before every release, including SSA’s printed 2027 payment dates, the CMS 2026 income tiers, and the hold-harmless and SSI rules. The calculation runs in your browser; nothing you type is sent to us.

Keeping it current

We check the figures against official sources on a schedule and whenever SSA or CMS makes an announcement. Every change is logged with the date, the old value, the new value and its source on the Sources page. Found a mistake? Tell us.

Figures last checked against official sources: