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The Higher Education Classification of Subjects (HECoS)

Subjects are persistent areas or branches of knowledge or learning that are studied in higher education. A new subject coding system - the Higher Education Classification of Subjects (HECoS) - has been implemented from 2019/20.  

HECoS replaces the Joint Academic Coding System (JACS).

On this page: Specification | Common Aggregation Hierarchy (CAH)Mapping | ImplementationManagement | Adoption | Background

Specification of HECoS

Download the HECoS vocabulary to view all subjects and their HECoS codes:

View the HECoS vocabulary

The HECoS vocabulary is (at the current version 9) a single flat (non-hierarchical) list of 1,092 subject terms that ensures the categorisation of courses and modules is always performed at a consistent level.

HECoS subject code identifiers are randomly generated and have no inherent meaning in themselves. Every HECoS code is associated with a subject term, a definition of that term, and where relevant, a scope note explaining the applicability of the code.

The complete HECoS vocabulary is available as downloadable Open data.

Common Aggregation Hierarchy (CAH)

The CAH is a grouping of subject codes

View a list of CAH groups

The Common Aggregation Hierarchy (CAH) provides a standardised hierarchical aggregation of HECoS codes suitable for the majority of uses. The CAH has been developed to provide standard groupings that can be applied to both HECoS and JACS subjects allowing for consistent analysis across both coding frames.

Read more about the CAH

Mapping documents

Mapping between subject coding frames can help in data analysis but should be used with caution. Not all coding related coding frames can be directly mapped to each other. The following links are to official mappings to or from HECoS and/or CAH.


HECoS was been developed independently from JACS and therefore there is no direct mapping available between the coding frames. To assist HE providers in recoding courses from JACS to HECoS, HESA produced two mapping documents to indicate suggested mappings that might be used:

Mappings from JACS3 to HECoS

Mappings from HECoS to JACS3


The Higher Education Funding Council for Wales (HEFCW) has published a mapping of HECoS to its Academic Subject Categories (ASCs), to complement existing mappings between JACS and ASCs.

Mappings of ASCs to HECoS (HEFCW)

LDCS and Price groups

The Office for Students (OfS) has produced mappings of HECoS and the Learn Direct Classification System (LDCS) to Price Groups to inform funding allocations.

Mappings of HECoS and LDCS to Price Groups (OfS)

Implementation of HECoS

It is important that data suppliers and data collectors adopt a consistent approach when implementing HECoS to ensure comparability of data across the sector. To promote consistency, we have produced an implementation guide to establish the key principles of HECoS allocation. This guide also addresses those specific areas where the basic allocation principles are insufficient, including in subject areas where specific funding and regulatory rules must be observed.

HECoS implementation guide

Management of HECoS and CAH

This document explains the process by which the HECoS standard is managed. It aims to provide confidence to users that the standard is stable and governed appropriately. It also delineates the parameters within which the HECoS standard can be adapted over time, and provides guidance to users who seek to update or improve HECoS.

Download the HECoS management guide

Adoption of HECoS and CAH

HECoS and CAH are published as Open Data, and the materials on this website are designed to support third party use in addition to aiding interpretation of HESA data. In addition to adoption by the HE sector, its agencies, funders, and regulators, HESA has supported the following government adoptions of the vocabulary:

The Academic Technology Approval Scheme (ATAS)

HESA supports the Foreign, Commonwealth and Development Office (FCDO) in their adoption of HECoS and CAH for the Academic Technology Approval Scheme (ATAS). This was implemented from 2019/20, to align with UCAS and HESA processes. We convened a meeting with the Foreign and Commonwealth Office (FCO, the FCDO's predecessor organisation) and volunteer HE providers to help determine an appropriate approach. Minutes from that meeting are available in the PDF below:

HECoS ATAS meeting January 2018

On 2021-05-06 the FCDO supplied HESA with a code mapping document, which came into effect on 2021-05-14, and which we have agreed to make available on their behalf in response to demand from our users. Whilst HESA works closely with the FCDO, we claim no responsibility for or ownership over the mapping available for download below. Any questions or queries regarding this information should be directed to the FCDO.

HECoS ATAS mapping

You can find further information about ATAS on the website or by contacting [email protected]

Student Loans' Company (SLC) and Student Support Regulations

The Student Loans Company (SLC) has adopted HECoS for use in course management information from the academic year 2019/20.

HECoS and CAH have been adopted for use as the definitional framework for implementation of funding rule exemptions for equivalent and lower qualifications in England, and part-time exceptions in Wales, in the relevant Student Support Regulations.

Development roadmap

The development roadmap specified in the HECoS management guide is coming close to completion. An updated roadmap and management guide will be prepared during 2021.

Transition from JACS to HECoS and background materials

Work began on the development of a new subject coding system in 2013 led by the former Higher Education Data and Information Improvement Programme (HEDIIP) and in consultation with the HE sector. The project was borne out of a need to replace the JACS system to meet the needs of a broader group of stakeholders and to reflect the diverse and dynamic nature of Higher Education in the twenty-first century, and culminated in July 2016 with the publication of the subject code system now known as HECoS.

View the HECoS archive

Open data

open-data   Open data licence: CC-BY-4.0