United Kingdom 76% open

Site specific forecasts for over 5,000 sites in the UK, including airports, major landmarks and beaches. Each site has the following weather forecast data available for it in 3-hourly intervals out to five days:

• Wind direction (16 point compass)
• Wind speed (mph)
• Screen temperature (degrees Celsius)
• Weather Type (weather ID)
• Visibility (code)
• Screen relative humidity (%)
• Wind gust (mph)
• Feels like temperature (degrees Celsius)
• UV Index (code)
• Precipitation Probability (%)

Met Office provides a restricted API to the forecast data. restrictions registration and used under licence. Data is provided in XML and JSON. Data is not available for bulk download.

HOWEVER the Cabinet Office provides an API to all of the data, with unlimited access: API on Azure Marketplace. The only requirement is that you register, which is reasonable when the Met Office data is about 20GB per day. Since there is no size restriction with this API, beyond technical constraints, you can easily download what you want, so that should be considered easy bulk access.

Some historic data is available for download but other historic data must be purchased.

The UK's Office for National Statistics has primary responsibility for maintaining and publishing national economic and demographic information (including the Census). ONS material is re-usable under the terms of the Open Government Licence and UK Government Licensing Framework. Each of the datasets is downloadable in full, machine-readable formats (mainly Excel, but some also available in CSV and XML).

Update: While you need to fill out a form in order to get access to the Ordnance Survey's Code-Point Open dataset, the Office for National Statistics publishes postcode data under an open licence publicly on the web.

Revision: you need to fill a form to get access to this dataset. Then you get a link by email.

Open postcode data which meets the specification here (postcodes and corresponding geospatial locations - lat/long or equivalent) is available via the Ordnance Survey's Code-Point Open dataset, which contains the 1.4m GB post codes each with a UK national grid reference of the postcode's location in eastings and northings (convertable to lat/long by published formulae) and with the administrative area (country/county/district/ward, plus National Health Service Region and Authority) in which it is located. This is updated quarterly. Similar Postcode data for the devolved province of Northern Ireland is not available as Open Data. The main UK address database (~24m individual addresses) is confusing called the Postcode Address File. This is a subscription-only database privately owned by the Royal Mail. The Open Data User Group have been pressing for its release too - see http://data.gov.uk/blog/dont-sell-our-postcodes-odug-on-why-we-should-have-open-addressing-in-the-uk The Postcode data as of August 2014 is available here: https://geoportal.statistics.gov.uk/Docs/PostCodes/ONSPD_AUG_2014_csv.zip The geographic coverage is United Kingdom (including Northern Ireland). More detailed information on the dataset can be found here: https://geoportal.statistics.gov.uk/geoportal/catalog/search/resource/details.page?uuid={473A5770-FB1B-4C1A-AEEC-5DC056E5EC7F}

Comment 2015: Didn't change from 2014. Link to products is here - http://www.ons.gov.uk/ons/guide-method/geography/products/postcode-directories/index.html

National map data is published by Ordnance Survey (https://www.ordnancesurvey.co.uk/) for Great Britain and is open data: https://www.ordnancesurvey.co.uk/opendatadownload/products.html

Ordnance Survey's OpenData suite of digital products includes 1:250,000 scale raster mapping for all of Great Britain, and additional national mapping at higher resolution (OS StreetView, OS Open Map - Local, OS Open Roads, OS Open Rivers and OS Boundary-Line).

The Ordnance Survey's OpenData product suite is released under the Open Government Licence, which complies with the Open Definition. The mapping is actively maintained and updated regularly.

As Ordnance Survey is the national mapping agency for Great Britain only, the coverage excludes Northern Ireland, the Isle of Man and the Channel Islands.

Separate national mapping data for Northern Ireland is produced by Ordnance Survey for Northern Ireland (OSNI) (http://www.nidirect.gov.uk/ordnance-survey-of-northern-ireland). However open data mapping for Northern Ireland is not currently available at resolutions of 1:250,000 or better.(http://www.nidirect.gov.uk/index/information-and-services/property-and-housing/your-neighbourhood-roads-and-streets/ordnance-survey-of-northern-ireland/product-range/digital-products.htm). OSNI mapping is available for re-use on commercial terms.

Legislation.gov.uk is a comprehensive public database of UK legislation maintained online by The National Archives, an executive agency of the Department for Culture, Media and Sport. The information is re-usable under the UK's Open Government Licence.

Machine-readable open data from Legislation.gov.uk is available through an API and as bulk downloads. PDF copies of legislation are also available in bulk.

Companies House, the public body responsible for maintaining company registers in the UK, has since June 2012 made available a subset of the fields of the register for all companies for bulk download as monthly 'snapshot', at no charge and on an open basis. The specifications for the data are documented at https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/370248/CompanyDataProductDataset.pdf and meets the minimum requirements of the definition of this element of the OKFN Census 2013. Additionally, full information from individual company registers is no longer subject to payment. Data is timely and was last updated on Oct 1st, 2015.

2015 - The budget breakdown can be found under PESA- Public Expenditure Statistical Analyses . However, it is not clear if one can see budget breakdown for sub-departments. Moreover, it was hard to find the dataset, and it was not available on data.gov.uk, but on the gov.uk website. In addition, there was no link from the treasury webpage to this dataset.

All the data is one place, but it would be better if it was in one spreadsheet.

The budget book can be find under the name Main Supply Estimates 2015 to 2016, and it is not publish in a Machine readable format, nor it does not linked from the treasury website.

In February 2015 the Cabinet Office launched a new version of Contracts Finder as a beta service. This service provides a search facility for public sector procurement contracts in England. Similar services are available for Scotland, Wales and Northern Ireland (though the NI service requires registration).

Cabinet Office has separately made available a static archive of data from the earlier version of Contracts Finder, covering the period from February 2011 to February 2015.

Information posted to Contracts Finder (past and present) is generally re-usable under the Open Government Licence but some contract records contain exceptions and are therefore non-open.

Realtime and recent historical data about observed levels of air pollutants and particulates at 128 automatic observing stations across the UK are at http://uk-air.defra.gov.uk. Pollutants covered include Ozone, Nitric oxide, Nitrogen dioxide, Nitrogen oxides as nitrogen dioxide, Sulphur dioxide, Carbon monoxide, PM10 particulate matter, Non-volatile PM10, Volatile PM10, PM2.5 particulate matter, Non-volatile PM2.5, and Volatile PM2.5. All this data is under the Open Government Licence. An RSS feed of latest data is available at http://uk-air.defra.gov.uk/rss/current_site_levels.xml , although this points to HTML pages such as http://uk-air.defra.gov.uk/data/site-data?f_site_id=ACTH&view=last_hour . The Data Selector http://uk-air.defra.gov.uk/data/data_selector allows a custom table to be constructed and either viewed or sent to the requestor as a CSV file. However there is a limit on the extent of the query (one test-drive for the Census gave "The selection you requested will return 1176 rows of data in 770 columns. This exceeds our limit of 256 columns."). This meets the Census requirement, apart from bulk download. In addition national estimates of annual emissions of 36 air pollutants from 1971-2011 are downloadable in CSV format under the Open Government Licence from http://naei.defra.gov.uk/data/data-selector, but again this is in the form of a table-builder and it does not seem possible to download all the data in bulk. Further public environmental data for the UK is maintained by several public bodies (mainly the Environment Agency for England and Wales, the Scottish Environmental Protection Agency, the Northern Ireland Environment Agency, plus Defra and DECC). Broadly speaking, data on major sources of pollutants is readily available via Government websites and public mapping applications. Some complete datasets are available as open data, notably from Defra: https://www.gov.uk/government/organisations/department-for-environment-food-rural-affairs/series/air-quality-and-emissions-statistics. Some environmental data is subject to additional licensing arrangements - see for instance http://www.geostore.com/environment-agency/WebStore?xml=environment-agency/xml/ogcDataDownload.xml

Reviewer 2014 - Data continues not to be available in bulk. Added link to the license.

2015: No changes from 2014.

Central Government departments are required to regularly publish lists of all financial transactions spending over £25,000; some departments publish transactions down to £500 or lower. The business rules and the format is described at http://webarchive.nationalarchives.gov.uk/20130129110402/http://www.hm-treasury.gov.uk/psr_transparency_index.htm The data is re-usable under the UK's Open Government Licence.

In addition summarised spending information by month x department x type of goods/services is available quarterly from the Treasury (Ministry of Finance) COINS/OSCAR database - see for instance https://www.gov.uk/government/collections/hmt-oscar-publishing-from-the-database This is also available under the Open Government Licence. The data was last updated/released in September 2014.

2014 reviewer comment: The data in no longer available through COINS or 'Where does my money go'. It can be found on data.gov.uk platform. I added the correct link to the information and a link to the data license.

2015 reviewer comment: OSCAR is not sufficient - it is an aggregation of transactions by budget code, not the detail of the transactions themselves. The monthly spend by government departments is scattered across gov.uk and data.gov.uk and is frequently out of date. For example at the time of writing the Cabinet Office itself is 12 months out of date: https://www.gov.uk/government/publications/cabinet-office-spend-data and http://data.gov.uk/dataset/financial-transactions-data-co (latest shown is August 2014, current date is September 2015.

There is little or no open data on land ownership available for the UK. Authoritative land ownership records are held by the Land Registry (England and Wales), Registers of Scotland and Land Registry (Northern Ireland). Individual records are available to the public for a fee. Records take the form of a title register (which identifies the owner and any rights of way or restrictions on the land) and a title plan (which defines the extents of the land). These are usually supplied in non-re-usable formats.

Data on properties in England and Wales owned by commercial and corporate entities is available in bulk and in a re-usable format, but on commercial terms rather than as open data.

Government agencies in each part of the UK also maintain ownership registers for agricultural land for purposes of compliance with the Single Payment Scheme (SPS), an agricultural subsidy scheme for farmers in the European Union. For example, the Rural Land Register for England is maintained by the Rural Payments Agency. These ownership records are not available for public re-use.

Land Registry has released a spatial dataset called INSPIRE Index Polygons that contains boundaries for registered freehold land and property in England and Wales. This dataset is available for public re-use but only the IDs attached to the boundaries are licensed as open data. The boundary polygons themselves are subject to additional licensing restrictions because they contain derived data from Ordnance Survey. The boundaries are not cadastral data and the dataset does not contain any ownership information.

Drinking Water Inspectorate (DWI) collects data from private companies in this link. It contains the following aggregated information:

• The Drinking Water Inspectorate Annual Report 2014 provides an overview of the quality of public and private water supplies in England and Wales.
• Regional reports covering the four regions of England and additionally Wales and summarising the testing and results of water quality tests, events and technical audit activity in the region. As you are aware there are examples of data for parts of the country available directly from the relevant water companies
• Private water supplies - Presented as separate reports for England and Wales and publishing numbers and types of supplies, a summary of monitoring results and case studies.
• Company data look up tables – data on each of the 27 private water companies
• Water Company Statistics
• Drinking Water Quality Events
• Prosecutions and Cautions

Data is not in weekly reports level, parameters are not from source level and is not in open formats.

The UK's Electoral Commission publishes an authoritative collection of electoral results (including general elections, local council elections and EU Parliament elections). The results are collected from local returning officers by a third party on behalf of the Electoral Commission. The Electoral Commission makes the bulk data available for download in CSV and Excel spreadsheet formats. In October 2013 the Electoral Commission updated the terms on its website to make it clear that the electoral data was re-usable under the Open Government Licence. Data is provided timely.

The data was last updated in May 2015 with results of the latest national elections.