Law Reports

Supreme Court Judgments
https://www.supremecourt.uk/decided-cases/

House of Lords judgments (Archive)
https://www.parliament.uk/about/how/business/judgments/

European Court of Human Rights judgments
https://www.echr.coe.int/Pages/home.aspx?p=caselaw/reports&c=

Westlaw (judgments database) - subscription site; most academic institutions permit students free access
https://www.login.westlaw.co.uk 

Lawtel (legal database) - subscription site; most academic institutions permit students free access
www.lawtel.com

Smith Bernal's Casetrack website - Judgments from the official shorthand writer to the court (Court of Appeal and Administrative Court). 
https://www.thelawyer.com/issues/4-may-1998/judgments-go-online-via-smith-bernal-web-site/