January
- 1 – Green New Year’s Resolution
- 5 – International Bird Day
- 9 – National Electricity Day
- 20 – Dr. Martin Luther King Jr. Day
February
- 2 – World Wetlands Day
- 20 – World Day of Social Justice
- 21 – International Mother Language Day
- 27 - International Polar Bear Day
- Black History Month
- Recyclemania
March
- 3 – World Wildlife Day
- 8 – International Women’s Day
- 14 – International Day of Action for Rivers
- 15 – World Consumer Rights Day
- 18 – Global Recycling Day
- 20 – International Day of Happiness
- 20 – Meatout Day
- 21 – International Day of Forests
- 21 – United Nations: International Day of Elimination of Racial Discrimination
- 22 – World Water Day
- 23 – World Meteorological Day
- Last Saturday of March – Earth Hour
- Women’s History Month
April
- 1 – Fossil Fools Day
- 2 – World Autism Awareness Day
- 3 – World Aquatic Animal Day
- 7 – World Health Day
- 18 – World Heritage Day
- 19-27 – National Park Week
- 20-26 – Dark Sky Week
- 22 – Earth Day
- Last Friday – National Arbor day
- Diversity Month
- Varies: Day of Silence
- Second Week: National Environmental Education Week
- Last Week: Air Quality Awareness Week
May
- Week Starting First Sunday – Drinking Water Week
- Week Starting First Monday – Screen-Free Week
- Week Starting Second Friday – National Groundwater Awareness Week
- Third Friday – Bike to Work Day
- 17 – International Day Against Homophobia, Transphobia, and Biphobia
- 20 – World Bee Day
- 21 – Endangered Species Day
- 22 – International Day for Biological Diversity
- 23 – World Turtle Day
- National Bike Month
- Mental Health Awareness Month
- Jewish American Heritage Month
- Asian American and Pacific Islanders Month
- Second Saturday – International Migratory Birds Day
June
- 5 – World Environment Day
- 7 – World Food Safety Day
- 8 – World Ocean’s Day
- 12 – World Day Against Child Labor
- 15 – Global Wind Day
- 17 – World Day to Combat Desertification and Drought
- 19 – Juneteenth
- 20 – World Refugee Day
- 22 – World Rainforest Day
- LGBTQ+ Pride Month
July
- 1-7 – National Clean Beaches Week
- 11 – World Population Day
- 28 – World Nature Conservation Day
August
- 8 – United Nations: International Day of the World’s Indigenous People
- 12 – International Youth Day
- 19 – World Humanitarian Day
- 20 – Ecological Debt Day
- 21 – National Honey Bee Day
- 26 – Women’s Equality Day
September
- 4 – National Wildlife Day
- 5- International Day of Charity
- 7 – International Day of Clean Air
- 10 – World Suicide Prevention Day
- 16 – International Day for the Preservation of the Ozone Layer
- 19 – National Cleanup Day
- 20 – United Nations: HeForShe
- 21 – Zero Emissions Day
- 21 – International Day of Peace
- 22 – World Car-Free Day
- National Hispanic Heritage Month
- National Recovery Month
- Third Saturday – International Coastal Cleanup Day
October
- First Monday – World Habitat Day
- 1 - World Vegetarian Day
- 2 – International Day of Non-Violence
- 4 – World Animal Day
- 6 – Energy Efficiency Day
- 10 – People with Disabilities: World Mental Health Day
- 11 – indigenous Peoples’ Day
- 11 – National Coming Out Day
- 16 – World Food Day
- 17 – International Day for the Eradication of Poverty
- 20 – Texas A&M Campus Sustainability Day Event
- 21 – LCBTQ+ Spirit Day
- 22 – World Planting Day
- 24 – International Day of Climate Action
- Global Diversity Awareness Month
- National Disability Employment Awareness month
- Breast Cancer Awareness Month
- First Week – Junk Mail Awareness Week
- LGBT History Month
- Vegetarian Awareness Month
- National Disability Employment Awareness Month
- Week of the 20th – Ally Week
November
- 1 – World Vegan Day
- 6 – International Day for Preventing the Exploitation of the Environment in War and Armed Conflict
- 15- National Recycling Day
- 16 – United Nations: International Day for Tolerance
- 17 – National Hiking Day
- 20 – LGBTQ+ Transgender Day of Remembrance
- Native American Heritage Month
- Movember
- Day After Thanksgiving – Buy Nothing Day
December
- 1 – World AIDS Day
- 2 – International Day for the Abolition of Slavery
- 3 – United Nations: International Day of Persons with Disabilities
- 5 – International Volunteer Day
- 4 - Wildlife Conservation Day
- 10 – United Nations: International Human Rights Day
- 20 – International Human Solidarity Day