The United Nations has declared 2021 as the International Year of Peace and Trust, the International Year of Creative Economy for Sustainable Development, and the International Year of Fruits and Vegetables.
Predicted and scheduled events
- April 19 – After 62 years of government by the Castro brothers, Raúl Castro is expected to step down as First Secretary at the Eighth Congress of the Communist Party of Cuba, which is scheduled to take place from April 16 to 19, 2021.
- May 6 – The 2021 UK local elections will see the whole country go to the polls for the first time other than in a general election.
- May 18 – May 22 – The Eurovision Song Contest 2021 will be held in Rotterdam, Netherlands after the cancellation of the 2020 contest due to the COVID-19 pandemic.
- May 26 – The second-shortest total lunar eclipse of the 21st century is expected to occur, lasting just 14 minutes and 30 seconds long.
- June 7 – The EU's Directive on Copyright in the Digital Single Market would likely to go effect, imposing copyright limitation for upload filters, link taxes and restriction on memes.
- June 10 – Annular solar eclipse.
- June 11 – July 11 – The UEFA Euro 2020 will be held across Europe, and the 2021 Copa América will be held in Argentina and Colombia. Both competitions were rescheduled from June 12, 2020 due to the COVID-19 pandemic.
- July 23 – August 8 – The 2020 Summer Olympics will be held in Tokyo, Japan. It was rescheduled from July 24, 2020 due to the COVID-19 pandemic.
- October 1 – The 2020 World Expo is scheduled to take place. It was rescheduled from October 20, 2020 due to the COVID-19 pandemic.
- October 23 – November 27 – The 2021 Rugby League World Cup will take place in England.
- October 31 – The James Webb Space Telescope is scheduled to be launched after being delayed several times.
- November - Planned launch of NASA's Artemis 1 mission to the Moon, the first integrated flight of the agency's Orion MPCV and Space Launch System rocket.
- November 1 – 12 – The 2021 UN Climate Change Conference will take place in Glasgow, Scotland. It was rescheduled from November 9, 2020 due to the COVID-19 pandemic.
- December 4 – Total solar eclipse.
- In the US, Brood X, the largest brood of North American seventeen-year cicadas, will emerge for the first time since 2004.
- Costa Rica is planned to become a completely carbon-neutral nation and ban "single use" plastic products.
- Amtrak's Avelia Liberty trains are expected to enter service in the US.
- In Canada, Toronto's Eglinton Crosstown light rail project is projected to be completed, and the first phase of the Réseau express métropolitain in Montreal is scheduled to open.
- Planned opening of the Dubai Creek Tower. Upon its completion it will become the world's tallest tower.
- Jeddah Tower is due for completion. Once completed it will become the world's tallest building and the first 1 km high building.
- The new Lagos–Ibadan Expressway in Nigeria is scheduled to be completed.
- Completion of the Dala Bridge in Yangon, Myanmar.
- The Grand Egyptian Museum, described as the largest archaeological museum in the world, is expected to be completed.
- Bangladesh is projected to eliminate extreme poverty, the first country in South Asia to do so.
- The 2021 Iranian presidential election is scheduled to be held.