http://www.legislation.gov.uk/ukpga/1980/66/section/12Highways Act 1980An Act to consolidate the Highways Acts 1959 to 1971 and related enactments, with amendments to give effect to recommendations of the Law Commission.1981-03-01texttext/xmlenStatute Law Database2026-03-18Expert Participation2026-03-13 Part II Trunk Roads, Classified Roads, Metropolitan Roads, Special Roads Classified roads General provision as to principal and classified roads.121Subject to subsection (3) below, all such highways or proposed highways as immediately before the commencement of this Act—awere principal roads for the purposes of any enactment or instrument which refers to roads or highways classified by the Minister as principal roads, either by virtue of having been so classified under section 27(2) of the Local Government Act 1966 (which is replaced by subsection (3) below), or by virtue of being treated as such in accordance with section 40(1) of the Local Government Act 1974,bwere (whether or not they also fall within paragraph (a) above) classified roads for the purposes of any enactment or instrument which refers to roads classified by the Minister (but does not specifically refer to their classification as principal roads), either by virtue of having been so classified under section 27(2) of the said Act of 1966, or by virtue of being treated as such in accordance with section 40(1) of the said Act of 1974, orcwere classified roads for the purposes of any enactment or instrument by virtue of being treated as such in accordance with section 27(4) of the said Act of 1966,continue to be, and to be known as, principal roads or, as the case may be, classified roads (or both principal roads and classified roads of a category other than principal roads, in the case of highways falling within both paragraph (a) and paragraph (b) above) for the purposes specified in subsection (2) below.2So far as a highway that continues to be a principal or classified road in accordance with subsection (1) above was, immediately before the commencement of this Act, a classified road for the purposes of any enactment repealed and replaced by this Act, it is a classified road for the purposes of the corresponding provision of this Act; and so far as any such highway was immediately before the commencement of this Act a principal or classified road for the purposes of any other enactment, or any instrument, it so continues for the purposes of that enactment or instrument.3The Minister may for the purposes of—aany provision of this Act which refers to classified roads, orbany other enactment or any instrument (whether passed or made before or after the passing of this Act) which refers to highways classified by the Minister,classify highways or proposed highways, being highways or proposed highways for which local highway authorities are the highway authorities, in such manner as he may from time to time determine after consultation with the highway authorities concerned.4References in any provision hereafter contained in this Act to classified roads are references to—aany highway or proposed highway that for the time being is a classified road for the purposes of that provision by virtue of subsections (1) and (2) above;bany highway or proposed highway that for the time being is classified under subsection (3) above for the purposes of that provision, or for the purposes of enactments that include that provision; andcany highway or proposed highway that for the time being is classified under subsection (3) above as a principal road for the purposes of any enactment or instrument which refers to roads or highways classified by the Minister as principal roads.1966 c. 42. 1974 c. 7. S. 12(3) modified (25.6.2025) by The M5 Junction 10 Development Consent Order 2025 (S.I. 2025/795), arts. 1, 14(3) (with arts. 4, 43, Sch. 9)S. 12(3) modified (12.10.2025) by The Gatwick Airport (Northern Runway Project) Development Consent Order 2025 (S.I. 2025/1054), arts. 1, 17(1) (with arts. 5, 9(6), 43, Sch. 9)