BS 7671

British Standard BS 7671 "Requirements for Electrical Installations. IET Wiring Regulations", informally called in the electrical community The "Regs", is the national standard in the United Kingdom for electrical installation and the safety of electrical wiring in domestic, commercial, industrial, and other buildings.

In general, BS 7671 applies to circuits supplied at nominal voltages up to and including 1000 volts AC or 1500 volts DC. The standard therefore covers the 230 volt 50 Hz AC mains supply used in the UK for houses, offices, and commerce. It did not become a recognized British Standard until the publication of the 16th edition in 1992.

The current version is BS 7671:2008+A3:2015 (the 17th edition incorporating Amendment 3:2015) issued in 2008 and updated ("Amendment no. 3") in January 2015 and mandatory from July 2015, although some provisions only came into force in January 2016. BS 7671 is also used as a national standard by Mauritius, St Lucia, Saint Vincent and the Grenadines, Sierra Leone, Sri Lanka, Trinidad and Tobago, Uganda, Cyprus, and several other countries, which base their wiring regulations on BS 7671.

The standard is maintained by the Joint IET/BSI Technical Committee JPEL/64, the UK National Committee for Wiring Regulations, and published by the IET (formerly IEE). Although the IET and BSI are non-governmental organisations and the Wiring Regulations are non-statutory, they are referenced in several UK statutory instruments, and in most cases, for practical purposes, have legal force as the appropriate method of electric wiring. The BSI (British Standards Institute) publish numerous titles concerning acceptable standards of design/safety/quality across different fields.

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