Glossary
Back-billing
Invoicing now for an increase that should have appeared on past invoices. Often not allowed.
Back-billing asks the customer to pay, on a later invoice, the difference that earlier invoices did not include. Some clauses allow a true-up. Many do not. They allow the new rate from a date forward and say nothing about reopening closed invoices.
Silence is not permission. If the clause does not authorize back-billing, the audit should label past months as missed and prospective, not as a receivable. Sending a surprise catch-up invoice is how a correct clause becomes a dispute.
Where a true-up is allowed, it is usually limited: a number of days, a requirement that notice had been given, or a prohibition on going back across a renewal. Quote the limit.
A useful audit separates three piles: dollars the clause lets you rebill, dollars you may charge from the next invoice forward, and dollars the window has already lost. Owners can decide. The piles should not be added together into one 'recovered' number.
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.