ISO 3166-2 assigns a standardized code to each principal administrative
subdivision of a country — a state, province, region, canton, or similar. The
code is the country’s ISO 3166-1 alpha-2 code, a hyphen, then a short local
suffix, like US-CA (California) or GB-SCT (Scotland). This lookup lets you
search across a curated set of subdivisions by country, name, or code.
How it works
Every ISO 3166-2 code has two parts joined by a hyphen. The prefix is the two-letter country code from ISO 3166-1 alpha-2. The suffix is one to three characters chosen by the country — usually a letter abbreviation of the subdivision name or a number from the local administrative numbering scheme.
The tool stores each subdivision with its country, full code, official name, and category (the local term: state, province, region, canton, emirate, etc.). Filtering matches the country code, the subdivision name, and the category, so you can search “California”, “US-CA”, or “state” and find the same entry.
Code formats by country — a comparison
Different countries chose very different suffix schemes when ISO 3166-2 was adopted. Here is how some major examples look:
| Country | Suffix scheme | Examples |
|---|---|---|
| United States | 2-letter postal abbreviation | US-CA, US-NY, US-TX |
| United Kingdom | 2–3 letter abbreviation | GB-ENG, GB-SCT, GB-WLS, GB-NIR |
| Germany | 2-letter Lander abbreviation | DE-BY (Bavaria), DE-BE (Berlin) |
| France | 2-digit department number | FR-75 (Paris), FR-13 (Bouches-du-Rhône) |
| Canada | 2-letter postal abbreviation | CA-ON (Ontario), CA-QC (Quebec) |
| Australia | 2–3 letter abbreviation | AU-NSW, AU-VIC, AU-QLD |
| Spain | 2-letter province abbreviation | ES-MD (Madrid), ES-CT (Catalonia) |
| China | 2-digit number | CN-11 (Beijing), CN-31 (Shanghai) |
Notice that some countries (France, China) use pure numbers as the suffix, while others (US, UK, Germany) use abbreviations derived from the local name. The standard imposes no single format — each country chose its own scheme.
Where ISO 3166-2 codes are used in practice
Address validation and postal services. Many international address standards reference ISO 3166-2 to specify the state or region unambiguously. E-commerce platforms and shipping APIs use these codes to validate and route parcels.
Geolocation and analytics. IP geolocation databases and analytics platforms tag visitor sessions with ISO 3166-2 subdivision codes so you can report by state or region without hard-coding local names in different languages.
Regulatory and compliance systems. Tax compliance (VAT/GST rates vary by Canadian province and Australian state, for example), insurance licensing, and medical device regulations all reference administrative subdivisions. ISO 3166-2 provides a lingua franca.
Software localization. When building locale selectors or regional settings, ISO 3166-2 codes provide stable identifiers that are independent of the local language — FR-75 remains FR-75 whether your UI is in English or French.
Caveats and staying current
ISO periodically updates 3166-2 when countries reorganize their administrative divisions, create new regions, or rename existing ones. Changes are published as online updates and newsletters by the ISO 3166 Maintenance Agency. This lookup covers the most commonly referenced subdivisions. For legally critical or exhaustive use — especially for large or frequently reorganized countries — cross-check against the official ISO Online Browsing Platform.
The country prefix is always the alpha-2 code from ISO 3166-1 (US, GB, etc.) — never the alpha-3 or numeric form. If you see USA-CA it is not a valid ISO 3166-2 code.