IANA Time Zones in Spain
For reliable scheduling, use the identifier that matches the place rather than a generic “Spain” setting. IANA identifiers contain historical transitions as well as present and future rules.
Why Does Mainland Spain Use CET?
Geography alone does not determine a country's legal clock. The Spanish Navy Observatory's official history records a one-hour advance on March 16, 1940. Mainland Spain did not return to its earlier relationship with Greenwich time after that change, and its modern legal-time system later became aligned with the European CET/CEST framework.
Longitude vs civil timeMuch of Spain lies west of the Greenwich meridian, yet legal time on the mainland is one hour ahead of UTC in winter.
Canary IslandsThe islands use the Western European clock family, maintaining a one-hour difference from peninsular Spain.
Modern schedulingUse current legal rules and IANA data rather than trying to infer Spanish time from longitude.