International Territorial Level

International Territorial Level (ITL) is a geocodestandard for referencing the subdivisions of the United Kingdom for statistical purposes, used by the Office for National Statistics (ONS). From 2003 and until 2020 it functioned as part of the European Union and European Statistical System's geocode standard Nomenclature of Territorial Units for Statistics or NUTS.

Following Brexit, the ONS set to develop a domestic statistical classification framework separate from NUTS. Initially, the ITLs were a mirror to the pre-existing NUTS system, they retained the same three level hierarchy and boundaries used for NUTS in the United Kingdom from 2018. ITLs were set to follow a similar review timetable to NUTS, being reviewed every three years. The ONS developed new official GSS codes of ITL geography aligned with the existing NUTS codes. From 1 January 2021, the ONS encouraged "ITL" be used as a replacement to the "NUTS" designation, with lookups between NUTS and ITL maintained and published until 2023.

The current ITL classification since 2025, has 12 regions at ITLs 1, 46 at ITL 2 and 182 at ITL 3.

The first ITL classification in 2021, following Brexit, was a mirror of the previous NUTS classification with slight modification, the ONS listed 12 regions at ITL 1, 41 regions at ITL 2, and 179 regions at ITL 3. "UK" in the NUTS codes were replaced with "TL".

The last NUTS classification is dated 21 November 2016 and was effective from 1 January 2018, listed 12 regions at NUTS 1, 40 regions at NUTS 2, and 174 regions at NUTS 3 level.