| International Day for Biological Diversity | | |
| Unity Day | | |
| Independence Day (2nd Day) | | |
| National Maritime Day | | |
| National Craft Distillery Day | | |
| National Solitaire Day | | |
| National Buy a Musical Instrument Day | | |
| National Vanilla Pudding Day | | |
| Emergency Medical Services for Children Day | | |
| Harvey Milk Day | | |
| World Goth Day | | |
| Sherlock Holmes Day | | |
| International Day to End Obstetric Fistula | | |
| Labor Day / May Day | | |
| Constitution Day | | |
| World Turtle Day | | |
| National Lucky Penny Day | | |
| National Taffy Day | | |
| Vlach’s National Day (for Vlach community) | | |
| Wesak - Buddha Day | | |
| Buddha Purnima | | |
| Buddha Purnima/Vesak | | |
| Vesak Full Moon Poya Day | | |
| Culture and Literacy Day | | |
| The Battle of Pichincha | | |
| Independence Day | | |
| National Aviation Maintenance Technician Day | | |
| Brother’s Day | | |
| National Scavenger Hunt Day | | |
| National Escargot Day | | |
| National Don’t Fry Day | | |
| Commonwealth Day | | |
| Saints Cyril and Methodius' Day | | |
| International Tiara Day | | |
| National Asparagus Day | | |
| National Title Track Day | | |
| National Day/May 1810 Revolution | | |
| Independence Day | | |
| Liberation and Resistance Day | | |
| Sing Out Day | | |
| Towel Day | | |
| National Missing Children's Day | | |
| National Wine Day | | |
| National Tap Dance Day | | |
| National Brown-Bag It Day | | |
| Africa Day | | |
| Geek Pride Day | | |
| Independence Day | | |
| National Sorry Day | | |
| World Lindy Hop Day | | |
| National Blueberry Cheesecake Day | | |
| Trinity Sunday | | |
| Lag B'Omer | | |
| Mother's Day | | |
| Carpet Day | | |
| Trinity | | |
| Dniester Day | | |
| Cultural Workers and Folk Artists Day | | |
| Kiev Day | | |
| National Paper Airplane Day | | |
| World Dracula Day | | |
| Sun Screen Day | | |
| National Cellophane Tape Day | | |
| National Grape Popsicle Day | | |
| Spring Bank Holiday | | |
| Day off for Commonwealth Day | | |
| Memorial Day | | |
| Jefferson Davis' Birthday | | |
| Mother's Day | | |
| Reconciliation Day | | |
| Late May Bank Holiday | | |
| Africa Day | | |
| Children's Day | | |
| Republic Day | | |
| Hamburger Day | | |
| Derg Downfall Day | | |
| National Brisket Day | | |
| Menstrual Hygiene Day | | |
| Amnesty International Day | | |
| International Day of United Nations Peacekeepers | | |
| Put a Pillow on Your Fridge Day | | |
| National Paperclip Day | | |
| National Coq Au Vin Day | | |
| National Senior Health & Fitness Day | | |
| National Flip Flop Day | | |
| National Biscuit Day | | |
| International Everest Day | | |
| Learn About Composting Day | | |