---
title: "Historic view of the earliest forecasted demand (NDF, TSDF) stream"
method: GET
path: "/forecast/demand/day-ahead/earliest/stream"
tags: ["Demand Forecast"]
---

# Historic view of the earliest forecasted demand (NDF, TSDF) stream

`GET /forecast/demand/day-ahead/earliest/stream`

This endpoint allows for retrieving a stream of earliest day-ahead demand forecast data from National Grid ESO.
Results are filtered by settlement time, and only the earliest published forecast for each settlement period is shown.
This endpoint has an optimised JSON payload and aimed at frequent request for the day-ahead demand forecast data.

## Query parameters

- `boundary` string
- `from` string, date-time, required
- `to` string, date-time, required

## Response `200`

Data retrieved

- InsightsApiModelsServiceDayAheadDemandForecastRow[]
  - `publishTime` string, date-time
  - `startTime` string, date-time
  - `settlementDate` string, date
  - `settlementPeriod` integer
  - `boundary` string, nullable
  - `transmissionSystemDemand` integer
  - `nationalDemand` integer, nullable

## Other responses

- `400` — Error with query parameters - see response for details
- `429` — Too many requests
- `500` — Server error - please try again later

---

[API](https://skmtc.net/elexon/apis/bmrs-insights.md) · [All operations](https://skmtc.net/elexon/apis/bmrs-insights/llms.txt) · [OpenAPI document](https://skmtc-service-staging.skmtc.workers.dev/v1/apis/elexon/bmrs-insights/revisions/d94e9edb295e/schema)