OPCS-4 is the groupings of concepts, with definitions, to classify interventions and surgical procedures for statistical purposes. It has business rules to maintain integrity of the classification structure as well as providing guidance on how the classification may be used.

OPCS-4 is a fully implemented and embedded NHS standard, mandated for use by Health Care Providers. It forms part of the NHS Standard Contracts.

The Standardisation for Care Information (SCCI) (now called Data Alliance Partnership Board (DAPB)) approved OPCS-4 as an NHS Fundamental Information Standard. 

NHS England develops, maintains and licenses OPCS-4 on behalf of the Department of Health.

Expand the below section to learn more about its purpose, benefits and how it's used in the NHS.

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  • provides the codes to summarise interventions and surgical procedures
  • enables classification of information derived from the patient record at the end of a hospital episode of care
  • focuses on what we 'count' for statistical and epidemiological analysis as well as reimbursement


  • captures snapshots of population health at a point in time and provides insights on trends, informs public health investments, service planning and reimburses hospitals for the care they have provided
  • hierarchical structure with sub-divisions allows statistical presentation of data, enabling useful and understandable information to be obtained
  • limited number of categories facilitates use in a statistical context
  • mutually exclusive categories reduces the possibility that events may be inadvertently excluded or counted more than once

How it's used

Reference Books

OPCS-4 must be used in combination with the associated Rules, Conventions, Standards and Guidance which are published in the OPCS-4 Reference Book. 

This is updated annually and published on Delen early each year to allow users to familiarise themselves with any changes made to the standards that must be used between 01 and 31 March each financial year.

Current and previous versions of the Reference Books are available in our Resource Library.

NHS Digital Classifications Browser

The NHS Digital Classifications Browser provides online access to the OPCS-4 Classification.

Find out more about the browser by visiting our Classifications Browser and eVersions page.

OPCS-4 Supplementary Information

Our OPCS-4 Supplementary Information document supplements the OPCS-4 standards and contains information about the more complex or less known procedures that are classified within OPCS-4.

Coders can build on this document by performing their own research and speaking with responsible consultants, clinicians and clinical staff within their Trust.

Current and previous versions of the documents are available in our Resource Library.

OPCS-4 eVersion

We provide electronic versions (eVersions) of OPCS-4 and ICD-10. These consist of the eViewer application into which eVersions of the classification books and standards can be improved and viewed.

More information is available on our Classifications Browser and eVersions page.

Training Resources

Broaden your coding knowledge by accessing our eLearning modules and presentations:

  • A Basic Introduction to Clinical Coding
  • Basic Anatomy and Physiology Module
  • Four Step Coding Process
  • SNOMED CT Awareness for Clinical Coders
  • Coding for Non Coders

Download OPCS-4 Data Files

OPCS-4 system data files and technical specifications for the NHS and NHS system supplier implementation are available to download from the TRUD website.

By visiting TRUD, you can also download:

OPCS-4.9 Tabular List Volume I and Alphabetical Index Volume II

The OPCS-4 Tabular List and Alphabetical are available to order from TSO online bookshop priced at £150 or with a 70% discount for NHS orders.

Submit an OPCS-4 Change Request

Help to keep OPCS-4 up to date by letting us know about any procedures, interventions and changes to clinical practice that impact classification codes via the Request Submission Portal

OPCS-4 Releases

OPCS-4 is updated every three years to facilitate provision of long-term statistical trends.

Previous versions are listed below, along with the financial year in which they were mandated for use. The implementation date for each version is always 01 April.

  • OPCS-4.10   2023 until further notice
  • OPCS-4.9      2020-2023
  • OPCS-4.8      2017-2020
  • OPCS-4.7      2014-2017
  • OPCS-4.6      2011-2014
  • OPCS-4.5      2009-2011
  • OPCS-4.4      2007-2009
  • OPCS-4.3      2006-2007
  • OPCS-4.2      Up to 31 March 2006

For information on OPCS-4 in the other UK Countries please contact the respective national centre:


The DAPB approved OPCS-4.10 for implementation on 01 April 2023.

Data files for NHS and system supplier implementation are available for download from TRUD, subject to registration and acceptance of the terms and conditions in November 2022.

The OPCS-4.10 High Level Release Roadmap provides information about key milestones for the release and indicates which dates are confirmed and which are subject to change. 

OPCS-4.10 High Level Roadmap
(Click on image to enlarge)

Products and Resources

The below products and resources will be made available and the OPCS-4.10 High Level Release Roadmap gives indicative dates of when they will be made available. 


How can I help to keep OPCS-4 up to date with clinical practice and request a change to the classification?

You can play a part in keeping OPCS-4 up to date by letting us know about new procedures, interventions and changes to clinical practice that impact classification codes via the Request Submission Portal.


How can I tell if a procedure has already been submitted?

Search submitted requests to find out. If your proposal is not recorded, login to NHS Digital RSP; read the Submissions Guidance and complete the form. Registration, if you are a new user, is quick and easy. You may find this example of a successful Request for Change helpful.


How can I get help with my submissions?

If you have any questions about completing the submission form or need advice on the suitability of your suggestion, email the Helpdesk. A member if the OPCS-4 Development Team will contact you.


Do you work with clinicians and their professional bodies?

The OPCS-4 Development Team works with clinicians and professional bodies to improve/update specialty content. Email the helpdesk, if you would like to explore this option.


Will SNOMED CT replace ICD-10 and OPCS-4?


SNOMED CT, ICD and OPCS-4 are nationally required standards that serve different but related and complementary purposes. In simple terms, SNOMED CT enables the detailed recording of information to support the provision of care, whereas ICD and OPCS-4 enable the statistically valid counting of diseases, other health conditions, interventions and procedures to support epidemiology and health care management.

Will clinical coders be needed once SNOMED CT has been implemented across the NHS?


Finished Consultant Episodes (FCEs) are coded by clinical coders, using the classifications products in accordance with national standards. The role of the clinical coder will evolve as electronic patient records (EPRs) become more common and as SNOMED CT and future classifications products (such as ICD-11) are implemented. However, the coding process requires experienced human beings to review the clinical notes, discuss with clinical colleagues and exercise judgement in the application of national standards to ensure that FCEs are coded reliably.

presentation on how SNOMED CT and clinical coding can work together is available in the Resource Library.

Will Clinical Coding Audit and Training be part of the Data Security and Protection Toolkit?


Both Acute and Mental Health Trusts are deemed ‘Large Organisations’ in the Data Security and Protection Toolkit (DSPT).

Clinical coders must refer to Data Security Standard 1 in the DSPT Assertion 1.7 Data Quality (Evidence codes 1.7.2, 1.7.3, 1.7.4) for clinical coding audit assertions and evidence requirements.

Clinical coders must refer to Data Security Standard 3 in the DSPT Assertion 3 Training (Evidence code 3.4.3) for clinical coding training, i.e. Specialist Training, assertions and evidence requirements.

Guidance is now available within our Resource Library on the Data Security Standard 3 Training and Data Security Standard 1 Data Quality for Acute and Mental Health Trusts.

For an Organisation to be Satisfactory they must complete all of the mandatory evidence items in their toolkit. Evidence items 1.7.2, 1.7.3 and 1.7.4 (covering clinical coding audit) and 3.4.3 (covering clinical coding training) are mandatory items.