What Is an ISIC Code? (ISIC Rev. 5) | International Industry Classification

Updated: 2026  |  Standard: UN International Standard Industrial Classification (ISIC)  |  Current revision reference: ISIC Rev. 5 (with Rev. 4 still common in implemented datasets)

What Is an ISIC Code?

An ISIC code is the United Nations’ global reference classification for grouping economic activity. ISIC is designed to support international comparability by giving countries and institutions a common activity framework for official statistics, industry analysis, and cross-border data harmonization.

In practice, ISIC often acts as the comparability layer between national and regional systems such as NAICS and NACE. It is most useful when you need to standardize industry data across countries, document revision context, or map local systems into a broader global reporting framework.

Convert ISIC to NAICS

Find likely NAICS matches for North American reporting or operational datasets.

ISIC-to-NAICS Conversion Tool →

Convert NAICS to ISIC

Translate regional North American activity codes into a global comparability layer.

NAICS-to-ISIC Conversion Tool →

Understand NACE alignment

See how Europe’s activity framework relates to ISIC in practical reporting contexts.

What Is a NACE Code? →

Practical scope: ISIC is primarily a statistical standard. Many businesses work directly with regional systems such as NAICS or NACE, then use ISIC as a comparability layer for international reporting and dataset harmonization.

Quick answer: ISIC, the International Standard Industrial Classification of All Economic Activities, is the UN’s global reference system for classifying economic activity.

It is used to support international comparability in official statistics, economic reporting, and multi-country datasets by grouping activity into a common hierarchy.

Global reference framework UN statistical standard Cross-country comparability Maps to NAICS and NACE Revision context matters

ISIC Rev. 5 in 2026: Status and Practical Use

ISIC Rev. 5 is the current UN-endorsed revision. In practice, many datasets, tools, and national implementations still reference ISIC Rev. 4 during transition planning and phased implementation. Because of that, the revision itself should be treated as part of the data’s provenance.

What to record

  • The ISIC revision used for coding
  • Any cross-revision mapping applied later
  • Whether the original code was assigned directly or converted from another system

Why it matters

  • Revision changes can refine industry boundaries
  • Longitudinal comparisons become weaker if revision context is missing
  • Crosswalk outputs should be treated as analytical mappings, not identities

Practical rule: start from the predominant activity, then validate difficult cases such as outsourcing, mixed-activity operations, or platform-enabled business models before finalizing a mapping.

ISIC Conversion and Lookup Tools

ISIC is often used to translate data between global and regional systems. These tools help with that workflow, but the output should still be validated against the unit’s primary activity and the relevant definitions.

ISIC-to-NAICS cross reference

Identify likely NAICS equivalents for North American datasets, reporting workflows, and operating models.

NAICS-to-ISIC cross reference

Translate NAICS to ISIC for global comparability, international benchmarking, and multi-country harmonization.

Workflow note: for multi-country datasets, standardize to ISIC and record the revision. Then map to NAICS or NACE when region-specific reporting is required.

How to Read an ISIC Code

ISIC is a four-level hierarchy that moves from broad sections to detailed classes.

Section (Letter) Division (2-digit) Group (3-digit) Class (4-digit)

Worked hierarchy example

This example shows how a detailed ISIC class nests within broader levels.

Section
C

Manufacturing

Division (2-digit)
13

Manufacture of textiles

Group (3-digit)
139

Manufacture of other textiles

Class (4-digit)
1393

Manufacture of carpets and rugs

ISIC Broad Structure (Top-Level Sections)

At the highest level, ISIC organizes the economy into sections. The section set below reflects the commonly used structure associated with ISIC Rev. 4, which remains a widely implemented baseline in many systems during transition planning.

Mobile tip: Scroll horizontally to view the full table.
Section Scope label Typical coverage
AAgriculture, forestry and fishingCrop and animal production, forestry, fishing and aquaculture
BMining and quarryingExtraction of minerals and mining support
CManufacturingTransformation of materials into products
DElectricity, gas, steam and air conditioning supplyUtilities production and distribution
EWater supply; sewerage, waste management and remediationWater and waste systems, remediation work
FConstructionBuilding, civil engineering, specialized trades
GWholesale and retail trade; repair of motor vehicles and motorcyclesDistribution, retail, and vehicle repair
HTransportation and storageTransport services, warehousing, logistics support
IAccommodation and food service activitiesHotels, lodging, restaurants, catering
JInformation and communicationPublishing, media, telecom, IT services
KFinancial and insurance activitiesBanking, insurance, auxiliary finance
LReal estate activitiesReal estate operations and services
MProfessional, scientific and technical activitiesLegal, accounting, engineering, R&D, consulting
NAdministrative and support service activitiesOffice support, facilities, travel, security
OPublic administration and defence; compulsory social securityGovernment administration and defence functions
PEducationSchooling and training
QHuman health and social work activitiesMedical services, residential care, social work
RArts, entertainment and recreationCultural activities, sports, recreation
SOther service activitiesMembership organizations, repair, personal services
TActivities of households as employers; undifferentiated goods- and services-producing activities of householdsHousehold employment and own-use production
UActivities of extraterritorial organizations and bodiesInternational organizations and similar bodies

Global vs. Regional Classification Systems

ISIC is global by design. NAICS and NACE are regional systems built for their own statistical and administrative environments. They often map to ISIC to support international comparability.

System Scope Primary role Common use cases
ISIC (UN) Global International comparability Cross-country reporting, global research, harmonizing multi-region datasets
NAICS North America Regional industry measurement U.S., Canada, and Mexico statistics, operational segmentation in North America
NACE European Union EU statistical and administrative alignment EU reporting, procurement and regulatory context, European datasets
SIC Primarily U.S. legacy Historical and legacy comparability Historical datasets and older administrative or vendor files

Conversion reality: a single ISIC code can map to multiple NAICS or NACE codes, and the reverse is also true. Crosswalks should be treated as candidate mappings, then validated against the unit’s primary activity and category definitions.

Applications of ISIC Codes

Economic and social statistics

Used in national accounts, employment analysis, productivity tracking, and structural business statistics.

Structural and comparative analysis

Used to monitor how industries change over time using a common activity framework.

Cross-border harmonization

Used to compare and align datasets that originate in different national coding systems.

  • Statistical unit assignment: classify establishments and enterprises to support reporting and comparability
  • Research and benchmarking: compare industry structure across countries and markets
  • Global reporting: create a common activity layer for multinational analysis

FAQ

  • Is ISIC used directly by businesses?
    ISIC is primarily a statistical standard. Many businesses work directly with regional systems such as NAICS or NACE and map to ISIC when cross-country comparability is needed.
  • What ISIC revision should I use in 2026?
    ISIC Rev. 5 is the current UN-endorsed revision, but ISIC Rev. 4 remains widely implemented in existing datasets. For defensible work, record the revision used and document any cross-revision mapping.
  • Can ISIC be converted to NAICS?
    Yes, but mappings can be non-unique. Convert, then validate the result against the unit’s predominant activity and the category definitions. ISIC-to-NAICS Conversion Tool
  • Can NAICS be converted to ISIC?
    Yes. This is common in multi-country reporting and harmonization. The result should still be checked against the organization’s primary activity. NAICS-to-ISIC Conversion Tool
  • How does ISIC relate to NACE?
    NACE is the European Union’s activity classification. It is designed to align with ISIC for international comparability while retaining EU-specific detail. What Is a NACE Code?

Guidance Sources

These sources provide UN definitions, published ISIC materials, and UN documentation related to ISIC Rev. 4 and Rev. 5. They are provided as guidance references.