Official sources · Questions

UK Statistics Authority and OSR: letters on the use of statistics

The UK Statistics Authority is the independent statutory body that oversees official statistics in the UK, and the Office for Statistics Regulation (OSR) is its regulatory arm. OSR publishes letters, casework outcomes, assessments and the list of accredited official statistics. For a fact-checker, its published letters to ministers, MPs and departments are the regulator's own written finding on how a specific statistic was used in public.

Covers: UK · Release calendar

What it publishes

• Public letters from the Authority Chair or OSR's Director General for Regulation to ministers, MPs, party leaders and departments about how a particular figure was presented in a speech, press release, social media post or debate.
• A searchable correspondence archive that can be filtered by correspondence type (casework, compliance check, Authority correspondence), by organisation (for example HM Treasury, Home Office or a political party) and by topic.
• A casework issues log in Excel, listing every case OSR has considered in the financial year with the date opened, a short title, the outcome (for example a published or private formal response) and the date closed.
• The Code of Practice for Statistics, including the Standards for Official Statistics and the Standards for the Public Use of Statistics, Data and Wider Analysis that OSR applies when judging how numbers were used.
• The list of accredited official statistics (called National Statistics in the Statistics and Registration Service Act 2007) and a separate list of accreditations that have been suspended, cancelled or reinstated.
• Assessment reports and compliance reviews that test individual sets of official statistics against the Code, with findings and required improvements.
• Systemic reviews of whole topic areas, an annual review of casework and quarterly management information on casework volumes and response times.
• Guidance for public bodies on intelligent transparency, on using management information in public statements and on statements about public funding.

Key datasets

• OSR correspondence archive
  Every published letter from or to OSR and the Authority, newest first, with sender, recipient and date. Covers the whole UK and runs back over many years; it can be filtered by type, organisation and topic.
  Updated: As issued, usually several letters a month
• Casework letters (filtered view)
  The correspondence archive restricted to casework, which is where OSR responds to concerns about specific statistical claims by governments, MPs and public bodies across the UK.
  Updated: As issued
• Authority Chair correspondence (filtered view)
  Letters sent by the Chair of the UK Statistics Authority, the route used when a case is raised by a parliamentarian or concerns wider political use of a figure. The same letters also appear on the Authority's own website.
  Updated: As issued
• Casework issues log
  Excel logs of all cases considered in the current and previous financial years (April to March), with an archive back to 2019. Each row gives the date opened, title, outcome and date closed, including cases handled privately.
  Updated: Weekly, aiming for each Wednesday
• Our Interventions Policy
  Sets out what OSR will and will not intervene on, the standards it applies, how it decides whether to publish, who signs letters and how it behaves during pre-election periods.
  Updated: Revised occasionally
• Code of Practice for Statistics
  The full Code, organised around Trustworthiness, Quality and Value, including the Standards for the Public Use of Statistics, Data and Wider Analysis that underpin judgements about public statements.
  Updated: Revised occasionally; the current edition is version 3.0
• Accredited official statistics lists
  Explains accreditation and links to the Excel list of all accredited official statistics across UK producers, plus the list of suspended, cancelled and reinstated accreditations with links to the related letters.
  Updated: Updated as accreditations change
• Assessment reports
  Formal assessments of named sets of statistics against the Code, which are the only route to accredited status. Covers producers in all four UK nations.
  Updated: As completed
• Compliance reviews
  Reviews of whether existing official statistics still meet the Code, often focused on a specific quality issue; they can lead to an accreditation being suspended or confirmed.
  Updated: As completed
• Annual review of casework 2025/26
  OSR's yearly summary of the cases it handled, the main themes in how statistics were used in public debate and how quickly it responded.
  Updated: Annual

APIs and downloads

• Correspondence RSS feed
  RSS (XML) feed of newly published letters. No key needed; suitable for alerts when a new casework letter appears.
• WordPress REST API for correspondence
  The site's public WordPress REST API returns letters as JSON, including title, date, link and body text. Change the search term in the URL; add per_page and page parameters to paginate. No key needed. This is the website's own interface rather than a documented statistical API, so field names may change.
• Publications RSS feed
  RSS feed of new assessment reports, compliance reviews, systemic reviews and other OSR publications. No key needed.
• Casework issues log 2026 to 2027 (Excel)
  XLSX file of the current year's cases. The file name changes when OSR uploads a new version, so link to the casework page for a stable route.
• List of accredited official statistics (Excel)
  XLSX list of all accredited official statistics by producer. The file name is dated and changes when the list is refreshed.
• Suspended and cancelled accreditations (Excel)
  XLSX table of accreditation decisions with current status and links to correspondence. The file name is dated and changes on update.

When it publishes

OSR does not run a fixed release calendar for letters: casework correspondence is published when a case concludes, often within days of a high-profile claim. The casework issues log is updated weekly, aiming for each Wednesday. The rolling regulatory work programme, which shows assessments and reviews in progress, is updated four times a year. During formal pre-election periods OSR can still intervene publicly, but only where a statement could significantly affect the debate presented to voters.

How to use it to check a claim

1. Start in the correspondence archive and filter by organisation (for example a department or a political party) and by topic before reading individual letters; filtering by type 'casework' removes routine compliance letters.
2. Use the site search or the REST API search with the subject of the figure (for example 'welfare spending' or 'waiting times') as well as the speaker's name, because letter titles usually name the recipient and the topic rather than the exact quote.
3. When you cite a letter, quote the regulator's own wording about the statistic and give the date, sender and recipient. Letters are signed by the Authority Chair when the case was raised by a parliamentarian or concerns wider political use, and otherwise usually by OSR's Director General for Regulation.
4. Check the casework issues log to see whether a concern about a figure is open, closed privately or closed with a published response. Inclusion in the log does not mean OSR shares the concern.
5. Before relying on a government statistic, check whether it is on the list of accredited official statistics and whether its accreditation has been suspended or cancelled; a suspended accreditation is a signal to read the related letter.
6. Read the Standards for the Public Use of Statistics, Data and Wider Analysis, which explain OSR's expectations: figures used in public should be published, sourced and given enough context for the public to understand them.
7. If you want OSR to look at a figure, email regulation@statistics.gov.uk or use the online form on the raise an issue page. OSR aims to acknowledge within one working day, then carries out an initial review, analysis, a judgement and a decision on whether to publish the outcome.

Common mistakes

• A letter from OSR records a judgement on how a statistic was presented and the context given; it does not rule on whether a policy is good or bad, and OSR states that it does not act as a mediator in political debate.
• Most OSR interventions are private, so the absence of a published letter does not mean no concern was raised; the issues log is the place to check.
• Accredited official statistics status applies to a named set of statistics, not to every figure a producer publishes, and 'official statistics in development' have not been through assessment.
• The older term 'National Statistics' and the newer 'accredited official statistics' describe the same status; the label changed in September 2023 but the legal term in the 2007 Act did not.
• Forecasts, impact assessments and unpublished management information are not routinely official statistics. OSR comments on their public use on an advisory basis, which carries a different weight from a finding about official statistics.
• Letters are dated and refer to the data available at the time; later revisions to the underlying statistics can change the picture, so check the current release before repeating an older finding.

Where can I find UK Statistics Authority letters to politicians about statistics?

They are published in the correspondence section of the OSR website, which can be filtered to show casework or letters from the Authority Chair, and narrowed by organisation such as a department or political party. Letters signed by the Chair also appear in the correspondence section of the UK Statistics Authority website. Each letter names the recipient, the statistic concerned and the date, and explains what the published data show.

Can a member of the public complain to the Office for Statistics Regulation?

Yes. Anyone can raise a concern by email to regulation@statistics.gov.uk, through the online form on the raise an issue page, or by post. OSR considers data and analysis published by UK governments, whether or not they are formally official statistics. It aims to acknowledge within one working day. The identity of the person raising a concern is kept confidential unless they agree otherwise.

What does accredited official statistics mean?

Accredited official statistics are official statistics that OSR has independently assessed and found to meet the Code of Practice standards of Trustworthiness, Quality and Value. The status is called National Statistics in the Statistics and Registration Service Act 2007, and the new label replaced that name in September 2023. OSR can suspend or cancel accreditation if it finds substantial non-compliance, and it keeps a public list of those decisions alongside the full list of accredited statistics.

Does OSR cover MPs and parties that are not in government?

OSR's statutory remit is official statistics and their use by producers and members of governments across the UK. Its interventions policy says it also expects parliamentarians outside government to meet the same standards as ministers when quoting statistics. It reviews party manifestos at general and local elections, and the Authority Chair has written to opposition party leaders and backbench MPs.

Questions answered using this source

• What are official statistics?
• What is the UK food inflation rate?
• How do I report misuse of statistics in the UK?
• What is the UK Statistics Authority?
• Is the Office for National Statistics reliable?

Links checked 2026-10-13. This page describes what the source publishes and gives no verdict on any claim.