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Editorial policy: how we research and update

Last updated November 12, 2026

Every rule, number and date on this site must trace back to an official source: OPM, the TSP, SSA, the IRS, the eCFR, the Federal Register or Congress. If we cannot verify something, we say so on the page.

Sources we use

Primary: opm.gov, tsp.gov and frtib.gov, ssa.gov, irs.gov, ecfr.gov, federalregister.gov, congress.gov (including CRS reports), and official agency releases. News outlets are used only as leads. We cite the primary source, or label the item as secondary or unconfirmed.

How a page is made

  • A writer prepares the page from primary sources and cites each fact.
  • Worked examples use the same formulas as our calculators.
  • An editor checks every fact against its cited source.
  • The page shows when it was last reviewed.

We update pages when COLAs, contribution limits, premiums or rules change.

Corrections

Corrections are made on the page, and significant ones are noted with the date.

Independence

Referral partners and advertisers have no say over our explanations of the rules or our calculator results.

Official sources