Longer than a bid window, which is the honest answer and the useful one. A measured carbon footprint depends on data you have to collect - energy, fuel, fleet, travel, and for scope 3 the suppliers who have to answer you in turn. None of that compresses well, and a figure produced in a hurry is the kind that gets challenged.
The practical route is to start before you need it. The Blue Award is free and gives you a modelled estimate from a company questionnaire, which is something to say while the measured work runs. The Silver Award produces a questionnaire-based scope 1, 2 and 3 report. Gold measures all company emissions through the NCZ data collection portal, with weekly assistance from the customer success team - that weekly cadence exists because data quality is where the time goes.
Platinum extends into the supply chain, which is the longest of the four because it depends on other organisations' reporting rather than your own, and the standard it is held to is engagement increasing year on year.
Because the levels stack, starting at Blue is not wasted work when the requirement arrives: it is the first stage of the same programme. NCZ's customer success team scopes the work with you, so the realistic date is something to ask about rather than to estimate from a page.
Last reviewed: September 2026