All APIs

UK nominal yield curve API

Bank of England nominal zero-coupon yields, from one source date to the full available curve. Retrieve one date or a paginated history.

One date. Explicit units.

Nominal zero-coupon yields, continuously compounded, published by the Bank of England. Values are decimal strings in percent and each curve contains the maturities available for that source date.

curl --request GET \
  --url "https://api.narwhalapi.com/v1/economics/GBR/yield-curve?date=2026-09-10&maturity=2y%2C10y" \
  --header "Authorization: Bearer $NARWHAL_API_KEY"

Example response Saved source sample · not a live request

{
  "country": "GBR",
  "curve_type": "nominal_zero_coupon",
  "date": "2026-09-10",
  "yields": [
    {
      "maturity": "2y",
      "yield_percent": "4.6509003413966044"
    },
    {
      "maturity": "10y",
      "yield_percent": "5.3572243604351168"
    }
  ]
}

Endpoints

GETBank of England nominal yield curves/v1/economics/{country}/yield-curve

country: USA is the only country in the verified yield archive.
date: Omit for the latest admitted observation. A supplied value selects that exact period; unavailable periods return 404.
version_id: Optional immutable publication version. Omit to read the current admitted curve.
maturity: Optional on both routes. Omit for the whole available curve. Allowed: 0.5y, 1y, 1.5y, 2y, 2.5y, 3y, 3.5y, 4y, 4.5y, 5y, 5.5y, 6y, 6.5y, 7y, 7.5y, 8y, 8.5y, 9y, 9.5y, 10y, 10.5y, 11y, 11.5y, 12y, 12.5y, 13y, 13.5y, 14y, 14.5y, 15y, 15.5y, 16y, 16.5y, 17y, 17.5y, 18y, 18.5y, 19y, 19.5y, 20y, 20.5y, 21y, 21.5y, 22y, 22.5y, 23y, 23.5y, 24y, 24.5y, 25y, 25.5y, 26y, 26.5y, 27y, 27.5y, 28y, 28.5y, 29y, 29.5y, 30y, 30.5y, 31y, 31.5y, 32y, 32.5y, 33y, 33.5y, 34y, 34.5y, 35y, 35.5y, 36y, 36.5y, 37y, 37.5y, 38y, 38.5y, 39y, 39.5y, 40y. Duplicates are removed and terms sorted; unsupported labels return 400.

MCP · economics_get_yield_curve

API reference →

GETBank of England nominal yield curves history/v1/economics/{country}/yield-curve/history

country: USA is the only country in the verified yield archive.
start: Inclusive lower bound. Omit for the first available period.
end: Inclusive upper bound; cannot precede start. Omit for the last available period.
limit: Default 100. Counts dates or years, not individual yield points.
cursor: Pass next_cursor unchanged with the same country, filters and limit. Cursors expire after 24 hours.
maturity: Optional on both routes. Omit for the whole available curve. Allowed: 0.5y, 1y, 1.5y, 2y, 2.5y, 3y, 3.5y, 4y, 4.5y, 5y, 5.5y, 6y, 6.5y, 7y, 7.5y, 8y, 8.5y, 9y, 9.5y, 10y, 10.5y, 11y, 11.5y, 12y, 12.5y, 13y, 13.5y, 14y, 14.5y, 15y, 15.5y, 16y, 16.5y, 17y, 17.5y, 18y, 18.5y, 19y, 19.5y, 20y, 20.5y, 21y, 21.5y, 22y, 22.5y, 23y, 23.5y, 24y, 24.5y, 25y, 25.5y, 26y, 26.5y, 27y, 27.5y, 28y, 28.5y, 29y, 29.5y, 30y, 30.5y, 31y, 31.5y, 32y, 32.5y, 33y, 33.5y, 34y, 34.5y, 35y, 35.5y, 36y, 36.5y, 37y, 37.5y, 38y, 38.5y, 39y, 39.5y, 40y. Duplicates are removed and terms sorted; unsupported labels return 400.

MCP · economics_get_yield_curve_history

API reference →

Work with the full history

Choose an inclusive start and end. Responses are oldest first, with up to 1,000 source dates per page. Follow next_cursor with the same filters and limit until it is null.

curl --request GET \
  --url "https://api.narwhalapi.com/v1/economics/GBR/yield-curve/history?start=2026-09-09&end=2026-09-10&limit=100&maturity=2y%2C10y" \
  --header "Authorization: Bearer $NARWHAL_API_KEY"

Example response Saved source sample · not a live request

{
  "country": "GBR",
  "curve_type": "nominal_zero_coupon",
  "observations": [
    {
      "date": "2026-09-09",
      "yields": [
        {
          "maturity": "2y",
          "yield_percent": "4.4821473122101274"
        },
        {
          "maturity": "10y",
          "yield_percent": "5.2493002729396405"
        }
      ]
    },
    {
      "date": "2026-09-10",
      "yields": [
        {
          "maturity": "2y",
          "yield_percent": "4.6509003413966044"
        },
        {
          "maturity": "10y",
          "yield_percent": "5.3572243604351168"
        }
      ]
    }
  ],
  "next_cursor": null
}

Missing maturities are omitted. Narwhal never fills a missing source point, substitutes an older curve, or invents a value.

A cursor preserves the publication snapshot for up to 24 hours. An expired or withdrawn snapshot returns 409; restart the request without its cursor.

Verified archive coverage

United Kingdom · GBR

GBR is the admitted country for this Bank of England contract.

2 Jan 1979 onward

Daily source dates; available terms vary historically

Yield in percent

Half-year terms from 0.5y to 40y; available terms vary by date.

The Bank of England aims to publish by noon Europe/London on the next business day. Weekends and holidays may have no new curve. Source values can be revised; a source check is not a promise of a new observation.

Sources and methodology

Bank of England · Yield curves

Nominal zero-coupon yields, continuously compounded, published by the Bank of England. Values are decimal strings in percent and each curve contains the maturities available for that source date.

Missing maturities are omitted. Narwhal never fills a missing source point, substitutes an older curve, or invents a value.

Narwhal attributes this dataset to the Bank of England and retains its published decimal values. The source may revise historical values; Narwhal validates a replacement before accepting it. Other countries may publish different curve measures, which are not included under this contract.