Tariff data and comparison methodology

Public tariff pages read a Postgres database filled by a separate collection process from Octopus Energy published product and rate data. The web application does not offer that database as a download or supported public API. Browser-only page helpers use versionless same-origin internal handlers; they are not public contracts.

Each family has a reviewed product-line rule. Pages resolve the version on sale for the relevant time and region; fixed products can be pinned when the family definition explains why. The exact product and tariff code is shown where it is needed to make the selection auditable.

Electricity pages use the 14 Grid Supply Point groups in Great Britain. Rates are shown for the selected region and in the unit returned for that tariff, normally pence per kWh including VAT. Gas, import and export values are kept separate because they describe different things.

Published-tariff calculators replay one shared evidence window and usage profile across eligible tariffs. Standing charges are included where available. Private comparisons keep account credentials and consumption in the browser. Results are estimates, not bills or switching quotes.

Calculations do not reproduce every supplier billing adjustment, discount, exit fee, dispatch override, device schedule, export credit, meter-register switch time or rounding rule. Each tool states its narrower exclusions next to the result.

A database failure is labelled unavailable, not absent. A conclusive empty result is treated separately. Tomorrow pages may check Octopus public rate data from the browser, but failure to reach that service never becomes a claim that rates have not been published.

OctoTariffs is independently operated and is not owned, operated or endorsed by Octopus Energy. It is an Octopus-only information and comparison service, not a whole-of-market service, and it is not presented as Ofgem Confidence Code accredited. Editorial conclusions are conditional on the evidence shown. Referral arrangements do not change ranking arithmetic, tariff coverage or the correction process.

Tools provide public evidence and bounded estimates, not supplier quotes, eligibility decisions, bills or regulated financial advice. A reader must verify current prices, product terms, equipment compatibility and account-specific availability with Octopus.

Carbon or renewable-generation statements name their data source, geography, time window and limitations. A low price is not treated as proof of low carbon, and correlation is not described as causation. This evidence-and-caveat approach follows the principles of the CMA Green Claims Code.

See the corrections policy to report a product, rate, calculation or explanation that appears wrong.