May 18 National Days

May 18 is the 138th day of the year (139th in leap years) in the Gregorian calendar, leaving 227 days until the end of the year. The celebrations on this date include tributes to public health, baked goods, playgrounds, musical talents, and even chocolate and peanut butter candies.

National Days on May 18th — May 18th National Days

Some of today’s observances—like Stepmother’s Day, Rural Life Sunday, and World Baking Day—are based on weekday placement, while others always fall on May 18.

Here’s a full overview of the 14 national and international days observed on May 18.

National and International Days on May 18

I Love Reese’s Day: Created in 2010 by The Hershey Company, this day honors the iconic peanut butter and chocolate candy first invented by H.B. Reese in the 1920s. Reese originally worked for Hershey before developing his own treat in his basement in Hershey, Pennsylvania. A fan-driven petition helped launch this annual celebration, which gives candy lovers a perfect reason to enjoy or share Reese’s in all its forms.

🍫 It joins other candy-themed days like National Candy Day on November 4 and World Chocolate Day on July 7.

International AIDS Candlelight Memorial* (Third Sunday in May): First held in 1983 in San Francisco and New York, this global event began as a grassroots response to the early HIV/AIDS crisis. Today, the memorial is coordinated by the Global Network of People Living with HIV and observed in communities around the world. The day honors those lost to AIDS, supports those living with HIV, and raises awareness about the ongoing challenges and efforts in the fight against the disease. Related events include World AIDS Day on December 1.

International Museum Day: Organized each year on May 18 by the International Council of Museums (ICOM), this day highlights the importance of museums in preserving cultural heritage and promoting public education. It has been observed annually since 1977 and now involves over 37,000 museums in more than 150 countries. Each year, a new theme guides events and exhibitions aimed at showcasing how museums serve as valuable tools for connection, learning, and global dialogue.

Mother Whistler Day: This playful observance encourages people to whistle throughout the day as a way to bring cheer and creativity into everyday moments. Though the origins are unclear, early mentions trace back to 1977 and a community in Huntingdon Valley, Pennsylvania, where locals marked May 18 as “Mother Whistler’s birthday.” Despite the name, it has no connection to the painting Whistler’s Mother and instead celebrates the joy of whistling itself.

National Cheese Soufflé Day: This food holiday shines a spotlight on the savory cheese soufflé, a French egg-based dish that puffs up when baked. The soufflé’s earliest mention dates to 1742 in Vincent La Chapelle’s Le Cuisinier Moderne, while chef Marie-Antoine Carême is credited with perfecting and popularizing the recipe by the 1800s. Cheese soufflés are among the most celebrated savory versions and share the culinary stage with similar days like National Cheese Day on June 4.

National HIV Vaccine Awareness Day: Launched in 1997 after a call to action by U.S. President Bill Clinton, this day recognizes the ongoing efforts to develop a preventive HIV vaccine. Coordinated by the National Institute of Allergy and Infectious Diseases (NIAID), the observance honors the many volunteers, scientists, and health workers involved in research. It also serves as a chance to educate the public and advocate for continued support and funding.

National No Dirty Dishes Day: A fun reminder to skip the cleanup or reduce dishwashing for a day, this lighthearted holiday encourages alternatives like disposable tableware, dining out, or simply minimizing mealtime mess. Though its exact origin is unknown, it shares the spirit of quirky, chore-free observances like National Lazy Day (August 10). It also serves as a playful excuse to simplify your routine, even just for one day.

Cleaning & Organizing National Days, Weeks and Months

National Speech-Language Pathologist Appreciation Day: First recognized in 2010, this day celebrates the professionals who help individuals improve communication and swallowing skills. The field began in the early 1900s with the founding of the American Academy of Speech Correction in 1925, which later became the American Speech-Language-Hearing Association (ASHA). These specialists play a vital role in healthcare and education, offering support for children and adults with speech and language challenges.

National Take Your Parents to the Playground Day * (Third Sunday in May): Founded in 2009 by the company PDPlay, this day encourages children to invite their parents to play outside and join in on the fun. It promotes family bonding and highlights the importance of outdoor physical activity for healthy development. The day also supports the broader goals of Children & Nature Awareness Month, which emphasizes the value of unstructured time in nature for young people.

National Visit Your Relatives Day: This observance encourages people to reconnect with family members they haven’t seen in a while. Whether it’s a quick visit, a phone call, or even a video chat, the day reminds us to maintain ties with relatives, especially those we may have lost touch with due to distance or busy schedules. It pairs well with National Siblings Day on April 10 and Grandparents Day, observed in September.

National Family and Relationship Days 2025

Ride a Unicycle Day* (Sunday of the Third Full Week of May): Established in 2017 by the Unicycling Society of America, this day celebrates both new and experienced unicyclists. It kicks off National Unicycle Week, an event designed to promote unicycling as a sport, a form of transportation, and a community activity. The observance offers a chance to try riding a unicycle, share tricks, or attend local meetups that support this niche hobby.

Rural Life Sunday* (Third Sunday in May): Introduced in 1929 by the United Methodist Church, this day honors the contributions of rural communities, especially farmers and agricultural workers. It reflects the church’s longstanding connection to rural life and recognizes the values of stewardship, sustainability, and faith-based service. The observance also acknowledges the influence of John Wesley, who often preached in rural settings during the early days of Methodism.

Stepmother’s Day* (Sunday after Mother’s Day): Founded in 2000 by nine-year-old Lizzie Capuzzi of Pennsylvania, this day honors the love and care of stepmothers. After writing to Senator Rick Santorum, Lizzie’s idea became part of the Congressional Record, and Stepmother’s Day gained wider recognition. The observance provides an inclusive way to celebrate blended families and acknowledge the unique bond between stepmoms and stepchildren.

World Baking Day* (Third Sunday in May): This sweet celebration began in 2012 and encourages people to bake something homemade and share it with others. Originally focused on cake, it now includes all types of baked goods, from cookies and pies to bread and muffins. The day promotes creativity in the kitchen and the joy of giving through food.

🧑‍🍳 This day is a companion to National Baker Day on September 23, National Homemade Bread Day on November 17 and World Bread Day on October 16.