The inspection data summary report (IDSR) is Ofsted's summary of the data available about a school. Ofsted's IDSR guide says inspectors use it when they are preparing for, and during, school inspections. It is not meant to be a complete picture of a school or a judgement of it. Ofsted says data is only the starting point for inspection, and that it does not make grading decisions on the basis of data alone.
Who produces it
Ofsted produces the IDSR. Most of the data in it comes from the Department for Education (DfE): the school census, the school workforce census, attendance and exclusions data, and the results of national tests and examinations. The school details at the start come from the DfE's Get Information about Schools service.
Who can see it, and where
You can open your school's IDSR through Ofsted's IDSR service or through the DfE's Analyse School Performance (ASP) service. You need a DfE Sign-in account with permissions for the school. Ofsted cannot give or remove that access. The approver for your school or organisation can help: in DfE Sign-in, open the 'Services' tab and choose 'See approvers at an organisation'.
The IDSR can contain sensitive information. Ofsted's conditions of use say:
- it is to be used only for educational and analytical purposes and for informing inspection
- its data is to be shared only with those who need it and are authorised to have access to it
- only nominated users may access it, and they cannot share it without permission from the data owner, which is the school or college
- it should be saved in a secure location with limited access.
Ofsted publishes example reports with made-up data for a fictional primary school and a fictional secondary school with a sixth form.
What it contains
The guide describes these parts:
- School details and the trust. For a school in a multi-academy trust, this includes the number of schools in the trust and their latest inspection outcomes.
- Context. School characteristics, ethnicity, special educational needs (SEN), year groups, prior attainment and staffing.
- Attendance and behaviour. Daily attendance, attendance, persistent absence, suspensions and permanent exclusions.
- Pupil movement and alternative provision. Pupils in Years 7 to 10 who were no longer at the school by the next January census, and alternative provision placements.
- Qualifications and achievement. Subject entries, then achievement in phonics and at key stage 2, key stage 4 and 16 to 18, each with summary tables and a fuller annex of tables and charts.
- Destinations. Sustained destinations after key stage 4 and after 16 to 18.
- Report card. The data that will eventually be presented alongside the inspection report.
An IDSR is produced for special schools, but it may contain very little information about pupils' performance. Since 13 February 2026 it has shown no national comparisons for special schools.
How to read the comparisons
For most measures, the IDSR compares the school's figure with the national figure for the same group of pupils. Disadvantaged pupils, for example, are compared with disadvantaged pupils nationally.
- Banding. A figure is 'Above' or 'Below' if it is more than 0.5 standard deviations above or below the national figure, and 'Close to average' if it is within 0.5 standard deviations.
- Significance. A confidence interval shows the range in which the school's true figure is likely to fall. If the whole interval sits above or below the national figure, the difference is significant ('sig+' or 'sig−'). If it crosses the national figure, it is not ('non-sig'). A figure can be 'Close to average' and still be significantly different from national.
- Colours. 'Above' and significant is usually green, 'Below' and significant usually red, and 'Close to average' or non-significant grey. For persistent absence and suspensions the colours are reversed.
- Small schools. For phonics and key stage 2, the IDSR averages results over 2 or 3 years where it can. Ofsted says this is particularly important in small schools, where a single pupil's outcome can disproportionately affect the data.
In the key stage 2 and key stage 4 tables, the IDSR also shows the gap between the school's disadvantaged pupils and non-disadvantaged pupils nationally, and whether it is 'Widening', 'Narrowing' or showing 'No meaningful change'.
Some progress measures skip recent years because of COVID-19 disruption. Key stage 2 progress uses 2022, 2023 and provisional 2026 data, because pupils who reached the end of key stage 2 in 2024 and 2025 did not sit key stage 1 assessments. Key stage 4 progress uses 2022 to 2024 data.
Similar schools, new from September 2026
Since 1 September 2026, the key stage 2 and key stage 4 achievement tables also compare each mainstream school with its own group of 50 similar schools. The DfE and Ofsted developed the similar schools model together. It matches schools on prior attainment, disadvantage, pupil numbers, stability, and the proportions of pupils with SEN support, an education, health and care (EHC) plan or English as an additional language.
The DfE says the similar schools data will not be used to make grading decisions. It adds an extra layer of information to support inspectors' understanding of a school's context and discussions about achievement and pupils' progress. The inspection toolkit lists, among the things inspectors consider, how pupils' attainment and progress in national tests and examinations compare with national averages and similar schools.
The comparison is not available for the phonics screening check or the multiplication tables check. The DfE says the same data, including the list of 50 similar schools, will also be in its upcoming digital platform for schools, which will not be publicly accessible.
How inspectors use it
- Before the inspection. The operating guide tells inspectors to review the IDSR alongside the previous inspection report, complaints made to Ofsted and the school's website, and to use that preparation to decide what to explore with leaders in the planning call.
- Data and on-site evidence together. Ofsted says inspectors never look at a single measure for a single year in isolation. The balance between the published data and on-site evidence is not fixed: it depends on the context and on how comprehensive and compelling the data is.
- Internal data. The toolkit says inspectors will not review internal data, though they may discuss with leaders how they use internal assessment data and what decisions they make as a result.
- Small cohorts and different intakes. The toolkit says published data for small cohorts is likely to fluctuate considerably. The operating guide tells inspectors to take account of the different age intakes of junior, middle and studio schools and university technical colleges.
- The draft report card. Inspectors are told to explain that, in the factual accuracy check, schools do not need to check data from other published sources.
The report card section
The last section of the IDSR shows the data that will eventually be presented alongside the report card: school and pupil context, the performance of all pupils and of disadvantaged pupils, the disadvantaged gap, destinations and absence. Provisional key stage 2 and 16 to 18 data does not appear there, because the DfE does not publish it. The section shows absence rather than attendance, so its bandings run the opposite way to those in the attendance section. Our Ofsted explainer covers report cards and grades.
When it is updated
Ofsted updates the IDSR during the year and lists each release on its IDSR news and updates page. That page lists 16 releases from 4 November 2025, when the IDSR changed for the renewed framework, to 25 September 2026.
- The 25 September 2026 release added 2026 provisional key stage 2 data, 2025 three-term exclusions data, 2026 one-term absence data and the latest staff turnover data.
- The next release is planned for October, with a spring census refresh including the latest children in need data, 2026 provisional key stage 4 and phonics data, and 2026 two-term absence data.
- Since March 2026 the attendance section has included a half-termly feed from the DfE's daily attendance collection, which schools share automatically through their management information systems. Ofsted does not receive daily attendance data for special schools.
What changed in 2025 to 2026
- November 2025. A new-style IDSR for the renewed framework, with a stronger focus on where a school sits within the national distribution.
- February 2026. Printing to PDF reintroduced: right-click on the IDSR.
- March 2026. Achievement summary tables redeveloped, and the gap trend method changed to take account of cohort sizes.
- September 2026. Reordering and format changes, with summary tables given priority, charts moved to a new annex, new attendance and behaviour summary tables and the similar schools comparison.
Official sources
- School inspection data summary report (IDSR) guide (Ofsted), last updated 25 September 2026
- IDSR: news and updates (Ofsted)
- The role of data on school and further education inspections (Ofsted blog, 7 November 2025)
- Similar schools model for attainment: overview (Department for Education)
- School inspection: toolkit, operating guides and information (Ofsted)
This page sets out what Ofsted's and the DfE's published documents say. It does not interpret your own school's data, and it is not advice on an individual case. Contains public sector information licensed under the Open Government Licence v3.0.
Spotted an error? Tell HeadteacherChat.
