EPSG:27700 — OSGB36 / British National Grid

Projected · UK - Britain and UKCS 49°45'N to 61°N, 9°W to 2°E

Export Formats

OGC WKT

PROJCS[
    "OSGB36 / British National Grid",
    GEOGCS[
        "OSGB36",
        DATUM[
            "Ordnance_Survey_of_Great_Britain_1936",
            SPHEROID["Airy 1830",6377563.396,299.3249646],
            EXTENSION["PROJ4_GRIDS","OSTN15_NTv2_OSGBtoETRS.gsb"]
        ],
        PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],
        UNIT["degree",0.0174532925199433,AUTHORITY["EPSG","9122"]],
        AUTHORITY["EPSG","4277"]
    ],
    PROJECTION["Transverse_Mercator"],
    PARAMETER["latitude_of_origin",49],
    PARAMETER["central_meridian",-2],
    PARAMETER["scale_factor",0.9996012717],
    PARAMETER["false_easting",400000],
    PARAMETER["false_northing",-100000],
    UNIT["metre",1,AUTHORITY["EPSG","9001"]],
    AXIS["Easting",EAST],
    AXIS["Northing",NORTH],
    AUTHORITY["EPSG","27700"]
]

WKT2

PROJCRS[
    "OSGB36 / British National Grid",
    BASEGEOGCRS[
        "OSGB36",
        DATUM[
            "Ordnance Survey of Great Britain 1936",
            ELLIPSOID[
                "Airy 1830",
                6377563.396,
                299.3249646,
                LENGTHUNIT["metre",1,ID["EPSG",9001]],
                ID["EPSG",7001]
            ],
            ID["EPSG",6277]
        ],
        ID["EPSG",4277]
    ],
    CONVERSION[
        "British National Grid",
        METHOD["Transverse Mercator",ID["EPSG",9807]],
        PARAMETER[
            "Latitude of natural origin",
            49,
            ANGLEUNIT["degree",0.0174532925199433,ID["EPSG",9102]],
            ID["EPSG",8801]
        ],
        PARAMETER[
            "Longitude of natural origin",
            -2,
            ANGLEUNIT["degree",0.0174532925199433,ID["EPSG",9102]],
            ID["EPSG",8802]
        ],
        PARAMETER[
            "Scale factor at natural origin",
            0.9996012717,
            SCALEUNIT["unity",1,ID["EPSG",9201]],
            ID["EPSG",8805]
        ],
        PARAMETER[
            "False easting",
            400000,
            LENGTHUNIT["metre",1,ID["EPSG",9001]],
            ID["EPSG",8806]
        ],
        PARAMETER[
            "False northing",
            -100000,
            LENGTHUNIT["metre",1,ID["EPSG",9001]],
            ID["EPSG",8807]
        ],
        ID["EPSG",19916]
    ],
    CS[Cartesian,2,ID["EPSG",4400]],
    AXIS["Easting (E)",east],
    AXIS["Northing (N)",north],
    LENGTHUNIT["metre",1,ID["EPSG",9001]],
    ID["EPSG",27700]
]

PROJ.4

+proj=tmerc +lat_0=49 +lon_0=-2 +k=0.9996012717 +x_0=400000 +y_0=-100000 +ellps=airy +nadgrids=OSTN15_NTv2_OSGBtoETRS.gsb +units=m +no_defs +type=crs

Proj4js

How to add a projection to Proj4js? →

proj4.defs("EPSG:27700", "+proj=tmerc +lat_0=49 +lon_0=-2 +k=0.9996012717 +x_0=400000 +y_0=-100000 +ellps=airy +nadgrids=OSTN15_NTv2_OSGBtoETRS.gsb +units=m +no_defs +type=crs");

JSON

{
  "type": "CoordinateReferenceSystem",
  "code": 27700,
  "name": "OSGB36 / British National Grid",
  "kind": "projected",
  "area": "UK - Britain and UKCS 49°45'N to 61°N, 9°W to 2°E",
  "unit": "metre",
  "bbox": [
    49.75,
    -9.01,
    61.01,
    2.01
  ],
  "proj4": "+proj=tmerc +lat_0=49 +lon_0=-2 +k=0.9996012717 +x_0=400000 +y_0=-100000 +ellps=airy +nadgrids=OSTN15_NTv2_OSGBtoETRS.gsb +units=m +no_defs +type=crs"
}

PostGIS

How to add a projection to PostGIS? →

INSERT INTO spatial_ref_sys (srid, auth_name, auth_srid, proj4text, srtext)
VALUES (27700, 'EPSG', 27700, '+proj=tmerc +lat_0=49 +lon_0=-2 +k=0.9996012717 +x_0=400000 +y_0=-100000 +ellps=airy +nadgrids=OSTN15_NTv2_OSGBtoETRS.gsb +units=m +no_defs +type=crs', 'PROJCS["OSGB36 / British National Grid",GEOGCS["OSGB36",DATUM["Ordnance_Survey_of_Great_Britain_1936",SPHEROID["Airy 1830",6377563.396,299.3249646],EXTENSION["PROJ4_GRIDS","OSTN15_NTv2_OSGBtoETRS.gsb"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.0174532925199433,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4277"]],PROJECTION["Transverse_Mercator"],PARAMETER["latitude_of_origin",49],PARAMETER["central_meridian",-2],PARAMETER["scale_factor",0.9996012717],PARAMETER["false_easting",400000],PARAMETER["false_northing",-100000],UNIT["metre",1,AUTHORITY["EPSG","9001"]],AXIS["Easting",EAST],AXIS["Northing",NORTH],AUTHORITY["EPSG","27700"]]');

MapServer

How to add a projection to MapServer? →

PROJECTION
  "+proj=tmerc"
  "+lat_0=49"
  "+lon_0=-2"
  "+k=0.9996012717"
  "+x_0=400000"
  "+y_0=-100000"
  "+ellps=airy"
  "+nadgrids=OSTN15_NTv2_OSGBtoETRS.gsb"
  "+units=m"
  "+no_defs"
  "+type=crs"
END

GeoServer

How to add a projection to GeoServer? →

27700=PROJCS["OSGB36 / British National Grid",GEOGCS["OSGB36",DATUM["Ordnance_Survey_of_Great_Britain_1936",SPHEROID["Airy 1830",6377563.396,299.3249646],EXTENSION["PROJ4_GRIDS","OSTN15_NTv2_OSGBtoETRS.gsb"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.0174532925199433,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4277"]],PROJECTION["Transverse_Mercator"],PARAMETER["latitude_of_origin",49],PARAMETER["central_meridian",-2],PARAMETER["scale_factor",0.9996012717],PARAMETER["false_easting",400000],PARAMETER["false_northing",-100000],UNIT["metre",1,AUTHORITY["EPSG","9001"]],AXIS["Easting",EAST],AXIS["Northing",NORTH],AUTHORITY["EPSG","27700"]]

Related Coordinate Systems

Available Transformations (10)

Transformation	Source → Target	Accuracy (m)
ETRS89 to OSGB36 / British National Grid (2)	4258 → 27700	0
ETRS89-GBR [OSNet v2009] to OSGB36 / British National Grid (3)	11009 → 27700	0
ETRS89 to OSGB36 / British National Grid (1)	4258 → 27700	0.2
OSGB 1936 / British National Grid to ETRS89 (1) Deprecated	27700 → 4258	0.2
OSGB 1936 / British National Grid to ETRS89 (2) Deprecated	27700 → 4258	0
OSGB 1936 / British National Grid to WGS 84 (2) Deprecated	27700 → 4979	1
OSGB 1936 / British National Grid to WGS 84 (1) Deprecated	27700 → 4326	1
OSGB 1936 / British National Grid to ETRS89 (3) Deprecated	27700 → 4258	0
OSGB 1936 / British National Grid to WGS 84 (2) Deprecated	27700 → 4326	1
OSGB36 / National Grid to WGS 84 (1) Deprecated	27700 → 4326	—

Other CRS using Ordnance Survey of Great Britain 1936

Frequently Asked Questions

How do I add EPSG:27700 to GeoServer?

Add the following definition to your GeoServer configuration:

27700=PROJCS["OSGB36 / British National Grid",GEOGCS["OSGB36",DATUM["Ordnance_Survey_of_Great_Britain_1936",SPHEROID["Airy 1830",6377563.396,299.3249646],EXTENSION["PROJ4_GRIDS","OSTN15_NTv2_OSGBtoETRS.gsb"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.0174532925199433,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4277"]],PROJECTION["Transverse_Mercator"],PARAMETER["latitude_of_origin",49],PARAMETER["central_meridian",-2],PARAMETER["scale_factor",0.9996012717],PARAMETER["false_easting",400000],PARAMETER["false_northing",-100000],UNIT["metre",1,AUTHORITY["EPSG","9001"]],AXIS["Easting",EAST],AXIS["Northing",NORTH],AUTHORITY["EPSG","27700"]]

Read the full GeoServer guide →

How do I add EPSG:27700 to PostGIS?

Add the following definition to your PostGIS configuration:

INSERT INTO spatial_ref_sys (srid, auth_name, auth_srid, proj4text, srtext)
VALUES (27700, 'EPSG', 27700, '+proj=tmerc +lat_0=49 +lon_0=-2 +k=0.9996012717 +x_0=400000 +y_0=-100000 +ellps=airy +nadgrids=OSTN15_NTv2_OSGBtoETRS.gsb +units=m +no_defs +type=crs', 'PROJCS["OSGB36 / British National Grid",GEOGCS["OSGB36",DATUM["Ordnance_Survey_of_Great_Britain_1936",SPHEROID["Airy 1830",6377563.396,299.3249646],EXTENSION["PROJ4_GRIDS","OSTN15_NTv2_OSGBtoETRS.gsb"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.0174532925199433,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4277"]],PROJECTION["Transverse_Mercator"],PARAMETER["latitude_of_origin",49],PARAMETER["central_meridian",-2],PARAMETER["scale_factor",0.9996012717],PARAMETER["false_easting",400000],PARAMETER["false_northing",-100000],UNIT["metre",1,AUTHORITY["EPSG","9001"]],AXIS["Easting",EAST],AXIS["Northing",NORTH],AUTHORITY["EPSG","27700"]]');

Read the full PostGIS guide →

How do I add EPSG:27700 to MapServer?

Add the following definition to your MapServer configuration:

PROJECTION
  "+proj=tmerc"
  "+lat_0=49"
  "+lon_0=-2"
  "+k=0.9996012717"
  "+x_0=400000"
  "+y_0=-100000"
  "+ellps=airy"
  "+nadgrids=OSTN15_NTv2_OSGBtoETRS.gsb"
  "+units=m"
  "+no_defs"
  "+type=crs"
END

Read the full MapServer guide →

How do I use EPSG:27700 with Proj4js?

Add the following definition to your Proj4js configuration:

proj4.defs("EPSG:27700", "+proj=tmerc +lat_0=49 +lon_0=-2 +k=0.9996012717 +x_0=400000 +y_0=-100000 +ellps=airy +nadgrids=OSTN15_NTv2_OSGBtoETRS.gsb +units=m +no_defs +type=crs");

Read the full Proj4js guide →

Type

Projected

Unit

metre

Geodetic CRS

OSGB36

Datum

Ordnance Survey of Great Britain 1936

Ellipsoid

Airy 1830

Prime Meridian

Greenwich

Area of Use

UK - Britain and UKCS 49°45'N to 61°N, 9°W to 2°E

United Kingdom (UK) - offshore to boundary of UKCS within 49°45'N to 61°N and 9°W to 2°E; onshore Gr…

Coordinate System

Cartesian 2D CS. Axes: easting, northing (E,N). Orientations: east, north. UoM: m.

WGS84 Bounds

61.01 -9.012.01 49.75

Data Source

EPSG

Information Source

Ordnance Survey of Great Britain.

Revision Date

2021-03-18

Scope

Engineering survey, topographic mapping.

EPSG

27700