May 20, 2026, is the 140th day of the year, with 225 days remaining, and it falls on a Wednesday — the third Wednesday of May — in the twentieth week of the year.
With 22 national and international days on the calendar, May 20 is anchored by World Bee Day, a UN observance on the birthday of the father of modern beekeeping, and Clinical Trials Day, marking the first controlled medical experiment in history conducted by James Lind in 1747. The third Wednesday in May also delivers a cluster of observances ranging from Employee Health and Fitness Day to International Customer Support Day, National Numeracy Day, and Turn Beauty Inside Out Day.
National Days on May 20
All national & international days celebrated today
22 celebrations on this dayWorld Bee Day
Proposed by Slovenia and adopted by the UN in 2017, World Bee Day falls on May 20 — the birthday of Anton Janša, the 18th-century pioneer of modern beekeeping. Bees and other pollinators contribute to one third of the world’s food production and are essential to biodiversity, yet face serious threats from pesticides, habitat loss, and climate change.
National Rescue Dog Day
Founded by Lisa Wiehebrink in 2018, National Rescue Dog Day on May 20 advocates for dog adoption from shelters and rescue organisations. Approximately 3.1 million dogs enter US shelters each year; around 390,000 are euthanised annually. The day encourages adoption over buying from breeders and celebrates the unique bond between rescue dogs and their new families.
Clinical Trials Day
Observed on May 20 to mark the anniversary of James Lind’s landmark 1747 clinical trial — the first controlled experiment in medical history, in which he tested six treatments for scurvy on twelve sailors aboard HMS Salisbury, discovering that citrus fruit was the cure. Clinical trials remain the gold standard for evaluating new treatments and have saved countless millions of lives.
World Metrology Day / Weights & Measures Day
Observed on May 20 — the anniversary of the signing of the Metre Convention in 1875 — World Metrology Day celebrates the science of measurement that underpins global trade, industry, science, and daily life. In 2019 the International System of Units was fundamentally redefined using fixed values of physical constants, marking the most significant change to measurement science in generations.
Here’s every observance celebrated on May 20, 2026.
National & International Days on May 20
Whether you’re adopting a rescue dog, picking strawberries, celebrating bees, thanking a band director, dreaming of becoming a millionaire, measuring something precisely, or baking a quiche Lorraine, here’s the story behind each of these May 20 celebrations.
Clinical Trials Day
Clinical Trials Day honors the first documented clinical trial conducted by British naval surgeon James Lind in 1747, which helped prove that citrus fruits could prevent scurvy. The modern observance was initiated in 2005 by the European Clinical Research Infrastructures Network (ECRIN), and later promoted by the Association of Clinical Research Professionals (ACRP) starting in 2014. The day recognizes the essential role of clinical research in advancing medicine and acknowledges the ongoing work of researchers, participants, and healthcare professionals worldwide.
Eat More Fruits and Vegetables Day
Eat More Fruits and Vegetables Day* (Third Wednesday in May) was founded in 2015 by the Dole Food Company to promote healthier eating habits by encouraging people to add more fruits and vegetables to their daily diet. With rising concerns over obesity and lifestyle-related diseases, this day highlights the health benefits of plant-based nutrition and aims to spark lifelong changes in food choices.
🌱 See also our separate list of national days dedicated to vegetarian and vegan diets.
Emergency Medical Services for Children Day
Emergency Medical Services for Children Day* (Third Wednesday in May) is part of National EMS Week. This day focuses on raising awareness about the need for specialized emergency care for children. It was founded by the federal EMSC Program in partnership with the American College of Emergency Physicians and the American Academy of Pediatrics. The goal is to improve how emergency services respond to the unique needs of critically ill or injured kids.
International Academic Freedom Day
International Academic Freedom Day was established in 2024 by Academics for Academic Freedom (AFAF) to promote the right of scholars and students to explore, teach, and publish ideas without fear of censorship or institutional repression. The date was chosen to mark the birthday of John Stuart Mill, author of On Liberty, a foundational work on free thought. Observed mostly in academic circles, it aims to raise awareness about ongoing challenges to intellectual independence in educational settings.
International Customer Support Day
International Customer Support Day* (Third Wednesday in May) recognizes the work of customer support professionals and their role in helping people solve problems every day. Founded in 2019 by Microsoft and its support partners, the observance—originally called Support Day—focuses on employee well-being, teamwork, and the connection between quality service, mental health, and sustainable business success.
International Red Sneakers Day
International Red Sneakers Day was founded in 2018 by the nonprofit Red Sneakers for Oakley™ to raise awareness about the seriousness of food allergies. It honors Oakley Debbs, an 11-year-old boy who tragically passed away in 2016 due to a severe allergic reaction to nuts. His signature red sneakers became the symbol of the campaign. The organization, started by his parents Merrill and Robert Debbs, uses this day to educate the public, advocate for better labeling, and promote allergy-safe practices.
National Employee Health and Fitness Day
National Employee Health and Fitness Day* (Third Wednesday in May) encourages workplaces to promote physical activity among employees. It was established to raise awareness about the health benefits of regular movement and is often marked by wellness events like fun runs, stretching breaks, and fitness classes. Companies are encouraged to support healthier lifestyles for their staff.
National Juice Slush Day
National Juice Slush Day* (Third Wednesday in May) was founded by Cool Tropics to celebrate frozen juice slush drinks, this day honors the playful creativity of icy beverages made with 100% fruit juice. While early versions date back to royal courts flavoring snow with crushed fruit, the modern slushie owes its invention to Omar Knedlik in the 1950s. His supercooled drink machine paved the way for billions of servings enjoyed by all ages.
National Band Director’s Day
National Band Director’s Day was established in 2020 by Russell Smith to recognize the vital role band directors play in shaping students’ musical growth and supporting arts education. The day encourages communities and schools to celebrate the dedication, mentorship, and lasting impact of band leaders across the country.
National Be a Millionaire Day
National Be a Millionaire Day invites people to reflect on financial goals and dream big. While its origins are unclear, the day has become a fun opportunity to explore the habits and planning strategies that can lead to wealth. It also encourages people to think about how they would use financial success for personal growth or social good.
💰 A related celebration, National Financial Awareness Day, takes place on August 14. I have designed dozens of free savings trackers you can download on DigitalHygge for free.
National High Heel Day
National High Heel Day was founded in 2021 by Kimberly Lorenz and Judge Gisela Laurent to celebrate high heels as symbols of empowerment and expression. More than a fashion statement, high heels often represent strength, identity, and confidence for many people. The day also promotes inclusivity and confidence in professional environments.
👠 Similar days that encourage self-expression through clothing are: National Dress Day on March 6, National Hat Day on January 15, and National Scarf Day on September 27.
National Numeracy Day
National Numeracy Day* (Third Wednesday in May) was launched in 2018 by the UK-based nonprofit National Numeracy to focuse on improving people’s confidence and skills with numbers. The organization, founded in 2012, aims to combat negative attitudes toward math and encourage practical approaches to improving numeracy. It’s a day for raising awareness of how basic math skills empower better decision-making in everyday life.
National Pick Strawberries Day
National Pick Strawberries Day celebrates the joy of harvesting fresh strawberries during peak season. Whether eaten raw, baked into desserts, or made into jam, strawberries offer both flavor and nutrition. This day complements National Strawberry Day on February 27, which marks the symbolic start of strawberry season, while this later date encourages people to enjoy the fruit freshly picked.
National Quiche Lorraine Day
National Quiche Lorraine Day honors a classic French dish made with a flaky crust, eggs, cream, bacon, and Swiss cheese. Originating in the Lorraine region—once under German rule—quiche Lorraine became popular outside France in the mid-20th century. Though many variations exist today, traditionalists insist the authentic recipe includes no vegetables or alternative meats.
National Rescue Dog Day
National Rescue Dog Day was started in 2018 by Lisa Wiehebrink, founder of Tails That Teach. It promotes the adoption of rescue dogs and highlights the transformative bond they create with their new families. Inspired by Cooper, a rescue pup from Los Angeles, the day raises awareness of shelter dog populations and encourages responsible pet ownership.
National Streaming Day
National Streaming Day was launched by Roku in 2014 to celebrate its 10th anniversary. It acknowledges how streaming services have changed the way we access entertainment. From music and movies to educational content, streaming platforms have made information and enjoyment more accessible. The observance also celebrates ongoing advances in technology and encourages users to explore new digital formats.
National SugarBee® Apple Day
National SugarBee® Apple Day has been celebrated since 2013 to honor the unique apple variety discovered by Chuck Nystrom in Worthington, Minnesota. This apple came from a chance pollination between a Honeycrisp and an unknown variety—thanks to a honeybee. With its caramel-like sweetness and long shelf life, SugarBee® apples have grown in popularity across the U.S. The day was established to celebrate this naturally created fruit and encourage consumers to enjoy its crisp texture and rich flavor.
🍎 Other apple-themed observances are: National Apple Day on October 21 and National Eat a Red Apple Day on December 1.
Turn Beauty Inside Out Day
Turn Beauty Inside Out Day* (Third Wednesday in May) was founded in 2000 by a group of girls aged 8 to 16 through New Moon Girls magazine. It challenges media-driven beauty standards by focusing on inner qualities like courage and compassion. It was launched in response to People magazine’s “50 Most Beautiful People” list. The aim is to redefine beauty to include traits like kindness, intelligence, and integrity.
National Women in Aerospace Day
National Women in Aerospace Day started in 2021 by Nikki Malcom, executive director of the Pacific Northwest Aerospace Alliance to recognize the vital contributions of women in aviation, aerospace engineering, and space exploration. It also promotes STEM opportunities for young girls and highlights the need for more representation in technical fields. Celebrations often include school events, industry talks, and community programs.
👩 Related observances include International Women in Engineering Day on June 23 and International Day of Women and Girls in Science on February 11.
World Autoimmune Arthritis Day
World Autoimmune Arthritis Day was created in 2012 by the International Autoimmune Arthritis Movement (now AiArthritis). This day brings attention to diseases where the immune system mistakenly attacks joints and tissues. Conditions like rheumatoid arthritis, lupus, and ankylosing spondylitis often go misdiagnosed or misunderstood. Through global events, patient stories, and advocacy, the day fosters understanding, drives research, and connects patients with resources.
🩻 World Autoimmune Arthritis Day complements awareness days like World Lupus Day on May 10 and World Arthritis Day on October 12.
World Bee Day
World Bee Day was declared by the United Nations in 2017 to shine a spotlight on the importance of bees and other pollinators. May 20 was chosen to mark the birthday of Anton Janša, a pioneer of modern beekeeping born in Slovenia in 1734. The day emphasizes the ecological role bees play in food security and biodiversity. With threats like habitat loss and pesticide use affecting bee populations worldwide, this observance encourages sustainable farming and pollinator-friendly practices.
World Metrology Day
World Metrology Day / Weights & Measures Day commemorates the signing of the Metre Convention in 1875, which laid the foundation for a unified international system of measurement. Seventeen nations came together that day to standardize units like the meter and kilogram. The celebration highlights the importance of accurate and consistent measurement in science, industry, and trade. Events are organized by national metrology institutes and the International Bureau of Weights and Measures (BIPM), connecting this day to ongoing advancements in measurement science.
