# OVO Energy

> OVO Energy is a United Kingdom household electricity and gas supplier founded in Bristol in 2009 and, after absorbing SSE's household energy business in January 2020, the third-largest domestic supplier in Great Britain with roughly four million home energy customers. It has NO public API: no developer portal, no API documentation, no machine-readable contract, and no third-party route to a customer's usage or billing data. This file is generated by API Evangelist from the catalog record and the live probe log — OVO Energy does not publish an llms.txt (https://www.ovoenergy.com/llms.txt returns 404).

Generated: 2026-07-27 | method: generated | source: apis.yml + review.yml + repo artifacts

## What a developer or agent needs to know first

- There is nothing to sign up for. No developer portal, no API key request form, no partner application, no data licence, no accreditation pathway.
- `api.ovoenergy.com` resolves and is live behind Cloudflare but answers every path with a bare `text/plain` 404: "No context-path matches the request URI." It is a gateway with no public context path.
- The only real consumer data endpoint found is undocumented and unsupported: `https://smartpaymapi.ovoenergy.com/usage/api/half-hourly` returns HTTP 401 JSON to an anonymous caller and serves half-hourly smart-meter consumption only to a signed-in OVO customer session. OVO staff have said on the company forum that these interfaces are for OVO/Kaluza internal use, are not public-facing, and may change or be withdrawn without notice.
- Great Britain mandated the metering INFRASTRUCTURE (Smart Energy Code, licensed Smart DCC), not a consumer data right. There is no GB equivalent of the Australian Consumer Data Right or Ontario's Green Button that would compel OVO to expose customer data through an API.
- Do not attribute Australian CDR obligations to this company. OVO Energy Pty Ltd (Australia) is a designated CDR energy data holder, but AGL Energy took it to 100% ownership in April 2024.
- Corporate change: on 11 May 2026 OVO agreed the sale of this UK retail business to E.ON (and Home Services to Hometree), subject to regulatory approval. The Kaluza platform is explicitly excluded from the sale.

## APIs

No public, documented APIs. `apis[]` in the catalog record is deliberately empty.

## Company

- [Website](https://www.ovoenergy.com/): OVO Energy retail and marketing site
- [About](https://www.ovoenergy.com/about): Company overview
- [OVO Group](https://company.ovo.com/): Parent group corporate site
- [Blog](https://www.ovoenergy.com/blog): Company blog
- [Careers](https://careers.ovo.com/): Engineering and other roles
- [LinkedIn](https://www.linkedin.com/company/ovoenergy)

## Customer surfaces (account holders only, not developer surfaces)

- [OVO customer portal](https://my.ovoenergy.com/login): the only route to your own energy data
- [Help centre](https://www.ovoenergy.com/help)
- [Customer forum](https://forum.ovoenergy.com/): the only place OVO staff discuss the internal APIs — and they discuss them to say they are not for public use

## Security

- [security.txt](https://www.ovoenergy.com/.well-known/security.txt): RFC 9116, expires 2026-12-31 — the only /.well-known document served anywhere on the estate
- [Responsible disclosure policy](https://www.ovoenergy.com/security): report via the Tines intake form; no bug bounty, conditional no-legal-action commitment
- [Privacy policy](https://www.ovoenergy.com/privacy-policy)
- [Terms](https://www.ovoenergy.com/terms)

## Open source

- [OVO Technology on GitHub](https://github.com/ovotech): 88 public repositories of internal engineering tooling — `laminar` (OpenAPI-first Node HTTP server), `castle`/`avro-*` (Kafka + Avro), `natchez-extras` (Scala tracing), `potygen`, `cloud-key-rotator`, `gitoops`. None of them is a product API definition or a client SDK for an OVO Energy API.

## API Evangelist artifacts in this repository

- `apis.yml` — the APIs.json 0.19 record for OVO Energy
- `review.yml` — the full anonymous probe log and mandate analysis behind the "no public API" verdict
- `well-known/ovo-energy-well-known.yml` — /.well-known probe index across five hosts
- `well-known/ovo-energy-security.txt` — verbatim RFC 9116 security.txt
- `security/ovo-energy-domain-security.yml` — TLS/HSTS/DNSSEC/CAA/SPF/DMARC posture for eight hosts and two domains
- `security/ovo-energy-vulnerability-disclosure.yml` — the responsible-disclosure programme, captured
- `conformance/ovo-energy-conformance.yml` — what OVO conforms to, and what it demonstrably does not
- `packages/ovo-energy-packages.yml` — first-party OVO Technology open-source libraries and the one community Python client

## Where GB energy data actually comes from

OVO publishes no open market data, which is structurally normal for a GB retailer. Open grid, market and system data in Britain comes from NESO, Elexon and the DNOs. A customer wanting their own smart-meter data programmatically can go around OVO entirely via a DCC "Other User" service such as n3rgy, Bright/Hildebrand or Loop.