Glossary
CPI adjustment clause
A clause that changes price by the ratio of two Consumer Price Index levels from a named series.
A CPI adjustment clause does not say 'charge whatever inflation was.' It points at an index. A complete clause names the population (CPI-U or CPI-W), the item (all items, or something narrower such as garbage and trash collection), the geography (U.S. city average or a metro), the seasonal treatment, and the two months being compared.
The arithmetic is a ratio of index levels, not a percent copied from a headline. Price × (index at the comparison month ÷ index at the base month). A floor and a cap, if the clause has them, are applied to that percent. See the CPI escalator calculator for the same method with published Bureau of Labor Statistics levels.
The usual commercial series is CPI-U, all items, U.S. city average, not seasonally adjusted: BLS series CUUR0000SA0. It is the right series only when the contract says so. A Denver clause, a Los Angeles clause, and a trash-collection clause are different series and different bills.
If the clause says only 'adjusted by CPI,' the honest finding is that the series is unspecified. Picking the national all-items index because it is familiar is a guess. Guesses do not go on an invoice.
Related terms
See it used in a worked example · CPI calculator · Request an audit
Sources and limits
Index levels from the U.S. Bureau of Labor Statistics Consumer Price Index, not seasonally adjusted, retrieved through the BLS Public Data API on November 1, 2026. Values are index points, not the headline 12-month percent.
Statewide rates reflect U.S. Department of Labor state minimum-wage postings as updated January 1, 2026, the U.S. Department of State Diplomatic Note on 2026 increases, and, for the prior-year comparison and named local rates, the National Employment Law Project compilation published in November 2025. Confirm the rate that applies to the workplace before using it in a bill.
The contracts in these worksheets are fictional. The prices are chosen so the arithmetic is easy to check. They are not a price survey and they are not client results.
RateClause is not a law firm. Nothing on this page is legal advice. Your clause controls, including whether a past period can be rebilled at all.
Primary postings: BLS Consumer Price Index, U.S. Department of Labor, state minimum wages, U.S. Department of State notice of 2026 minimum-wage increases.