| May 2018 | |||
|---|---|---|---|
| Date | Day | Holiday | Where |
| May-1 | Tuesday | Alaska Agriculture Day | Alaska (Special Days) |
| May-1 | Tuesday | Cold War Victory Day | Maine (Special Days) |
| May-1 | Tuesday | Family Day | Alaska (Special Days) |
| May-1 | Tuesday | Law Day | Nevada (Special Days) |
| May-1 | Tuesday | Lei Day | Hawaii (Special Days) |
| May-1 | Tuesday | Loyalty Day | South Carolina (Special Days) |
| May-3 | Thursday | Alaska Day of Prayer | Alaska (Special Days) |
| May-3 | Thursday | Commonwealth Day of Prayer | Virginia (Special Days) |
| May-4 | Friday | Arbor Day | North Dakota, Vermont (Special Days) |
| May-5 | Saturday | Green Up Day | Vermont (Special Days) |
| May-7 | Monday | Hemophilia Awareness Day | Arkansas (Special Days) |
| May-8 | Tuesday | Primary Election Day | Indiana (Public Holidays) |
| May-8 | Tuesday | Truman Day | Missouri (Public Holidays) |
| May-9 | Wednesday | Public School Paraprofessional Day | Texas (Special Days) |
| May-9 | Wednesday | Willie Velasquez Day | Texas (Special Days) |
| May-10 | Thursday | Confederate Memorial Day | South Carolina (Public Holidays) |
| May-10 | Thursday | Saint Damien de Veuster Day | Hawaii (Special Days) |
| May-11 | Friday | Day of recognition for early childhood and day-care providers and professionals | Virginia (Special Days) |
| May-11 | Friday | Military Spouse Appreciation Day | Delaware (Special Days) |
| May-11 | Friday | Native American Day | Wyoming (Special Days) |
| May-11 | Friday | Vietnam Human Rights Day | Virginia (Special Days) |
| May-12 | Saturday | Fibromyalgia Awareness Day | South Carolina (Special Days) |
| May-13 | Sunday | Mother's Day | Iowa, Kansas, Nevada, North Dakota, Virginia (Special Days) |
| May-14 | Monday | Mother's Day | American Samoa (Public Holidays) |
| May-15 | Tuesday | Peace Officers Memorial Day | Georgia (Special Days) |
| May-19 | Saturday | Armed Forces Day | Oregon (Special Days) |
| May-21 | Monday | Yellow Ribbon Day | Utah (Special Days) |
| May-22 | Tuesday | Maine Merchant Marine Day | Maine (Special Days) |
| May-23 | Wednesday | Crohn's and colitis awareness | Ohio (Special Days) |
| May-25 | Friday | Missing Persons Day | Maine (Special Days) |
| May-28 | Monday | Memorial Day | Federal (Federal Holidays) |
| May-28 | Monday | Memorial Day | New York Stock Exchange (NYSE Holidays) |
| May-28 | Monday | Memorial Day | Alabama, Alaska, Arizona, Arkansas, California, Colorado, Connecticut, Delaware, Florida, Georgia, Hawaii, Idaho, Illinois, Indiana, Iowa, Kansas, Kentucky, Louisiana, Maine, Maryland, Massachusetts, Michigan, Minnesota, Mississippi, Missouri, Montana, Nebraska, Nevada, New Hampshire, New Jersey, New Mexico, New York, North Carolina, North Dakota, Ohio, Oklahoma, Oregon, Pennsylvania, Rhode Island, South Carolina, South Dakota, Tennessee, Texas, Utah, Vermont, Virginia, Washington, West Virginia, Wisconsin, Wyoming (Public Holidays) |
| May-28 | Monday | Memorial Day | US Banks (US Bank Holidays 2018) |
| May-28 | Monday | Memorial Day | United States Postal Service (USPS Holidays) |
| May-28 | Monday | Washington Day | Virginia (Public Holidays) |