# New York Independent System Operator (NYISO)

> NYISO operates New York State's bulk electricity grid, administers the state's wholesale energy, capacity and ancillary-services markets, and does long-term power system planning. Its data posture is two-speed: the market and system data archive is completely open and anonymous, while its only true REST APIs are restricted to registered market participants behind an MIS account plus a NAESB digital certificate. NYISO publishes no OpenAPI, no GraphQL, no MCP server and no webhooks; API documentation is distributed as PDF user guides. Generated by API Evangelist on 2026-07-27 from probe-verified sources — every URL below returned a live response on that date.

## Open data — no key, no account, no sign-up

- [MIS public data archive](http://mis.nyiso.com/public/): roughly 58 report families as dated CSV plus monthly ZIP bundles. Anonymous HTTP/HTTPS.
- [MIS report index](http://mis.nyiso.com/public/menu.htm): the catalogue of report families and their P-codes.
- [Energy Market & Operational Data hub](https://www.nyiso.com/energy-market-operational-data): the human entry point.
- [OASIS postings](https://oasis-postings.nyiso.com/): FERC Order 889/890 transmission postings in an anonymously listable object store, history back to 1999.
- [OASIS front end](http://oasis.nyiso.com/): single-page application over the same postings.

### URL convention for the archive

- Daily file: `http://mis.nyiso.com/public/csv/<report-dir>/<YYYYMMDD><report-name>.csv`
- Monthly bundle: `http://mis.nyiso.com/public/csv/<report-dir>/<YYYYMM01><report-name>_csv.zip`
- Current snapshot (some reports): `http://mis.nyiso.com/public/csv/<report-dir>/current<ReportName>.csv`

### Most-used reports (verified 2026-07-26 files)

- [Day-ahead zonal LBMP (P-2A)](http://mis.nyiso.com/public/csv/damlbmp/20260726damlbmp_zone.csv)
- [Day-ahead generator LBMP (P-2B)](http://mis.nyiso.com/public/csv/damlbmp/20260726damlbmp_gen.csv)
- [Real-time zonal LBMP (P-24A)](http://mis.nyiso.com/public/csv/realtime/20260726realtime_zone.csv)
- [Real-time actual load (P-58B)](http://mis.nyiso.com/public/csv/pal/20260726pal.csv)
- [Integrated real-time actual load (P-58C)](http://mis.nyiso.com/public/csv/palIntegrated/20260726palIntegrated.csv)
- [Real-time fuel mix (P-63)](http://mis.nyiso.com/public/csv/rtfuelmix/20260726rtfuelmix.csv)
- [ISO load forecast (P-7)](http://mis.nyiso.com/public/csv/isolf/20260726isolf.csv)
- [Real-time ancillary services prices (P-6B)](http://mis.nyiso.com/public/csv/rtasp/20260726rtasp.csv)
- [Day-ahead ancillary services prices (P-5)](http://mis.nyiso.com/public/csv/damasp/20260726damasp.csv)
- [Day-ahead scheduled outages (P-54C)](http://mis.nyiso.com/public/csv/outSched/20260726outSched.csv)
- [Generator names reference](http://mis.nyiso.com/public/csv/generator/generator.csv)
- [Load names reference](http://mis.nyiso.com/public/csv/load/load.csv)
- [Active transmission nodes reference](http://mis.nyiso.com/public/csv/activetransmissionnodes/activetransmissionnodes.csv)

## Market-participant REST APIs — credentialed, 401 to everyone else

- [Finance APIs User's Guide v1.2 (PDF)](https://www.nyiso.com/documents/20142/45334160/NYISO%20Finance%20APIs%20User's%20Guide%20v1.2%20-%20DRAFT.pdf/4f0de58a-783d-a317-64fe-caed77ba61fa): Metering, Settlements and Invoicing.
- [Metering API User Guide (PDF)](https://www.nyiso.com/documents/20142/27889215/NYISO%20Metering%20API%20User%20Guide.pdf/d8ed36d3-1a40-9584-6961-3fdb845ca4fa)
- [Market Participant User's Guide (PDF)](https://www.nyiso.com/documents/20142/3625950/mpug.pdf): MIS accounts and NAESB digital certificates.
- [Settlement Data Applications User's Guide (PDF)](https://www.nyiso.com/documents/20142/3625950/SDA_UG.pdf): account privileges.
- Production roots: `https://api.nyiso.com/finance/metering/`, `/finance/settlements/`, `/finance/invoicing/`, `https://api.nyiso.com/metering/`
- Market-trial root: `https://apitest.nyiso.com/finance/` (also credentialed)
- Auth: HTTP Basic with an MIS user account **plus** the NAESB certificate bound to that account, on every request, over TLS 1.2+.

## API Evangelist artifacts in this repo

- [Authentication profile](authentication/nyiso-authentication.yml)
- [API conventions](conventions/nyiso-conventions.yml)
- [Error catalogue](errors/nyiso-problem-types.yml)
- [Lifecycle and deprecation](lifecycle/nyiso-lifecycle.yml)
- [Sandbox / market trial](sandbox/nyiso-sandbox.yml)
- [Standards conformance](conformance/nyiso-conformance.yml)
- [Data model and full report catalogue](data-model/nyiso-data-model.yml)
- [Derived JSON Schemas for ten CSV reports](json-schema/)
- [Third-party packages](packages/nyiso-packages.yml)
- [Domain security probe](security/nyiso-domain-security.yml)
- [Well-known probe record](well-known/nyiso-well-known.yml)
- [Agent skills](skills/_index.yml)

## Optional

- [Manuals, tech bulletins and user guides](https://www.nyiso.com/manuals-tech-bulletins-user-guides)
- [Billings and settlements](https://www.nyiso.com/billings-and-settlements)
- [Real-time dashboard](https://www.nyiso.com/real-time-dashboard)
- [NYISO blog](https://www.nyiso.com/blog)
- [Legal notice](https://www.nyiso.com/legal-notice)
- Stakeholder Services: Stakeholder_Services@nyiso.com, +1 518-356-6060

## What NYISO does not have

No OpenAPI or Swagger anywhere (probed on every host). No GraphQL. No MCP server. No webhooks, events or AsyncAPI. No OAuth 2.0, OpenID Connect or API keys. No `/.well-known/` documents of any kind, including no security.txt. No first-party SDK or CLI. No public Postman collection. No status page. No consumer or retail customer data — NYISO is a wholesale system operator and holds no retail customer relationships, so Green Button and ESPI do not apply to it.