United Kingdom of Great Britain and Northern Ireland
Includes England, Scotland, Wales, Northern Ireland) (KD - Eng & Wales; KDC - Scotland; KDE - No. Ireland)
VLex Justis (laws, cases, statutory documents - Yale network only)
LLMC Digital (Historical)
ICLR Online Library (Publications of the Incorporated Council of Law Reporting (ICLR) for England and Wales. In addiition to the official Law Reports, ICLR publishes the Weekly Law Reports, the Industrial Cases Reports, the Business Law Reports, the Public and Third Sector Law Reports, and the Consolidated Index to leading law reports)
Legislation.gov.uk (legislation and statutory instruments); Gov.uk (official documents; command papers)
UK Parliament (publications)
Northern Ireland Case Database
Scottish Courts (case law database)
JustCite (An open-access neutral citator for UK and EU (and ECHR) material, including cases, statutes, legislation, treaties, scholarly articles, and more; it links your search to case law, legislation and articles from numerous third-party publishers, and shows how they relate to each other)