The National Archives on behalf of HM Government, legislation.gov.uk
legislation.gov.uk provides all legislation from 1988- and "most pre-1988 primary legislation." Most primary legislation is available in "revised" form, which includes amendments. This free site only includes statutory instruments from 1988-. This site is now the official place of publication for recently enacted UK legislation. Additional information about scope of available material appears in the FAQs.
The search feature allows researchers to retrieve statutes and statutory instruments by title, by year of enactment, and by type of legislation.
Westlaw provides statutes and statutory instruments currently in force.
After retrieving a statute, be aware that link: Analysis yields commencement/status information and amendments, as well as citing cases and (often) cites to journal articles/books.
Westlaw: United Kingdom Law in Force Historic
Westlaw also includes historic versions (from 1992-) of statutes and statutory instruments, "including company commercial, intellectual property, tax, personal injury, litigation and county court rules consolidated by the editors at Sweet & Maxwell." (Derivation: Consolidated Law in Force published by Sweet & Maxwell.)
Lexis Advance provides statutes and statutory instruments currently in force. (Derivation: Halsbury’s Statutes, published by LexisNexis Butterworths.)
Path: LexisNexis for Law School > tab: Go to Lexis Advance > Explore Content: International > United Kingdom > United Kingdom Legislation > Statutes of England & Wales
After retrieving a statute, be aware that: Notes (commencement/status information and amendments) appear at the end of the text.
Path: LexisNexis for Law School > tab: Go to Lexis Advance > Explore Content: International > United Kingdom > United Kingdom Legislation > Statutory Instruments of England and Wales
Justis provides statutes (1235-), statutory instruments (1949-) and earlier regulations (1671-) in original form.
Justis (PDF) (campus/dorm use or implement proxy instructions) > click: Continue to Justis
ACCESS TIP: There are no usernames and passwords for Justis. BLS researchers who have implemented the proxy instructions should click the tab: "Continue to Justis."
Search template allows one to retrieve an act or regulation.
Tab: Index and Contents > click "+" in front of: Legislation to access a “drill down” menu to retrieve an act or statutory instrument by year/title.