Price creep: how a signed contract gets more expensive without anyone deciding it should

Contracts do not stay the price you signed. Four mechanisms move them, and all four are legal, disclosed, and sitting in the document today. Escalator clauses raise prices on a schedule — a fixed percentage each year, or a formula tied to an inflation index — and they compound for the life of the agreement. Evergreen clauses renew the contract automatically unless someone objects inside a notice window, which means the escalators renew too, without a negotiation ever happening.

Then there are the mechanisms between renewals. Product substitution: the contracted item is discontinued or “upgraded,” and its replacement arrives at a new price that never went through sourcing. And surcharges: freight, fuel, handling — line items added to invoices mid-term that were never in the negotiated unit price. Each one is small. Together, across hundreds of line items and a few years, they are how a hard-won contract quietly returns to where it started.

None of this is hidden. It goes uncaught for structural reasons: the person who negotiated the deal has often moved on, and the institutional memory of what was agreed leaves with them. The renewal notice window — often 90 days or more before term end — passes silently because no calendar was watching it. And accounts payable pays what is invoiced; matching an invoice against negotiated terms line-by-line is nobody’s daily job.

The volume of line items is the real cover. A price move on one SKU among thousands is invisible in a monthly spend report. The drift only becomes visible when someone reconstructs unit prices over time for a category — at which point the question is always the same: how long has this been happening?

The fix is not heroic analysis; it is a renewal calendar with owners. Every contract, its end date, its notice window, and a name responsible for opening the negotiation before the window closes. Renegotiation timed to the notice window is leverage; renegotiation after an evergreen rollover is a request.

At each renewal, three asks belong on the table by default: a cap on any escalator, price protection for a defined period, and substitution approval rights — no replacement item at a new price without sign-off. These are standard terms. Suppliers grant them routinely when asked at the right moment, and almost never volunteer them.