Earth Hour 2040 Countdown

When is Earth Hour 2040?

Earth Hour 2040 is counted down to Saturday, March 31, 2040 at 12:00 AM UTC. The canonical URL keeps the year in the path, so Earth Hour 2040 and Earth Hour 2041 are separate target-date pages.

Plan across time zones

• Earth Hour uses the last saturday in march rule.
• Publish local event times, venue details, and campaign cutoffs separately from the public date.
• Use UTC as the canonical event timezone for this countdown.