| Human Rights Day | |  |
| Constitution Day | | |
| Dewey Decimal System Day | | |
| Jane Addams Day | | |
| National Lager Day | | |
| Nobel Prize Day | | |
| Anniversary of Victory over ISIS | | |
| Hanukkah Ends | | |
| International Animal Rights Day | | |
| Human Rights and Peace Day | | |
| International Mountain Day | | |
| Anniversary of the Statute of Westminster | | |
| Republic Day | | |
| National App Day | | |
| National Noodle Ring Day | | |
| Birthday of the Sultan of Selangor | | |
| Independence Day | | |
| Gita Jayanti | | |
| National Have A Bagel Day | | |
| Day of Neutrality | | |
| Feast of Our Lady of Guadalupe | | |
| Jamhuri Day | | |
| National Ambrosia Day | | |
| National Ding-a-Ling Day | | |
| Gingerbread House Day | | |
| Poinsettia Day | | |
| International Day Of Neutrality | | |
| International Universal Health Coverage Day | | |
| National Day | | |
| Republic Day | | |
| National Guard Birthday | | |
| National Cocoa Day | | |
| National Violin Day | | |
| Pick A Pathologist Pal Day | | |
| National Salesperson Day | | |
| Friday the 13th | | |
| Official Lost and Found Day | | |
| Day Of The Horse | | |
| National Bouillabaisse Day | | |
| Monkey Day | | |
| National Wreaths Across America Day | | |
| Gingerbread Decorating Day | | |
| International Shareware Day | | |
| Roast Chestnuts Day | | |
| National Cupcake Day | | |
| Cat Herders Day | | |
| National Wear Your Pearls Day | | |
| Bill of Rights Day | | |
| Third Advent Sunday | | |
| Homecoming Day (only Alderney) | | |
| Dhanu Sankranti | | |
| National Day | | |
| Independence Day | | |
| National Chocolate Covered Anything Day | | |
| Day of Reconciliation | | |
| Barbie and Barney Backlash Day | | |
| Las Posadas | | |
| Stupid Toy Day | | |
| National Day (2nd day) | | |
| Independence Day (Day 2) | | |
| Pan American Aviation Day | | |
| Wright Brothers Day | | |
| National Maple Syrup Day | | |
| Saturnalia December | | |
| Arabic Language Day | | |
| National Day | | |
| Nigerien Republic Day | | |
| International Migrants Day | | |
| National Roast Suckling Pig Day | | |
| Answer The Telephone Like Buddy The Elf Day | | |
| Bake Cookies Day | | |
| Gluten-Free Baking Week | | |
| Remembrance Day for Roma and Sinti killed by Genocide | | |
| National Hard Candy Day | | |
| National Oatmeal Muffin Day | | |
| National Re-Gifting Day | | |
| National Heroes and Heroines Day | | |
| Orthodox St. Nicholas Day | | |
| National Emo Day | | |
| Macau S.A.R. Establishment Day | | |
| International Human Solidarity Day | | |
| Abolition of Slavery | | |
| National Sangria Day | | |
| National Ugly Christmas Sweater Day | | |
| Underdog Day | | |
| Mudd Day | | |
| December Solstice | | |
| Games Day | | |
| Go Caroling Day | | |
| International Dalek Remembrance Day | | |
| National French Fried Shrimp Day | | |
| Crossword Puzzle Day | | |
| Humbug Day | | |
| Phileas Fogg Win A Wager Day | | |
| National Homeless Persons’ Remembrance Day | | |
| National Flashlight Day | | |
| Yule | | |
| December Solstice | | |
| Dongzhi Festival | | |
| Turkish Language Day (Turkish community) | | |
| National Short Story Day | | |
| Don’t Make Your Bed Day | | |
| National Coquito Day | | |
| Ribbon Candy Day | | |
| Look On The Bright Side Day | | |
| National Short Girl Appreciation Day | | |
| Unity Day | | |
| National Date Nut Bread Day | | |
| Forefathers Day | | |
| Fourth Advent Sunday | | |
| Sambisa Memorial Day | | |
| Mathematics Day | | |
| National Cookie Exchange Day | | |
| National Short Person Day | | |
| National Pfeffernusse Day | | |
| National Roots Day | | |
| Festivus | | |
| Emperor's Birthday | | |
| Christmas Eve | | |
| Independence Day | | |
| Yap Constitution Day | | |
| National Eggnog Day | | |
| Christmas | | |
| Constitution Day | | |
| Christmas Day | | |
| Grav Mass Day | | |
| A'phabet Day or No "L" Day | | |
| National Pumpkin Pie Day | | |
| Boxing Day | | |
| Family Day | | |
| Synaxis of the Mother of God | | |
| Independence and Unity Day | | |
| Day of Goodwill | | |
| National Day of Thanksgiving | | |
| Proclamation Day | | |
| National Candy Cane Day | | |
| National Thank You Note Day | | |
| National Whiner’s Day | | |
| Hanukkah Starts | | |
| Kwanzaa (1st Day) | | |
| Day After Christmas Day | | |
| St. Stephen's Day | | |
| Second Day of Christmas | | |
| Constitution Day | | |
| National Fruitcake Day | | |
| Christmas Holiday | | |
| Hanukkah II | | |
| Visit The Zoo Day | | |
| Make Cut-Out Snowflakes Day | | |
| International Day Of Epidemic Preparedness | | |
| Holy Innocents | | |
| Day of the Holy Innocents | | |
| Republic Day | | |
| National Short Film Day | | |
| National Chocolate Candy Day | | |
| National Card Playing Day | | |
| Pledge of Allegiance Day | | |
| Hanukkah III | | |
| Incwala Day | | |
| National Call A Friend Day | | |
| Independence Day | | |
| National Pepper Pot Day | | |
| Tick Tock Day | | |
| Feast of the Holy Family | | |
| Hanukkah IV | | |
| Day of the Declaration of Slovakia as an Independent Ecclesiastic Province | | |
| National Bacon Day | | |
| National Bicarbonate of Soda Day | | |
| Falling Needles Family Fest Day | | |
| Hanukkah V | | |
| Rizal Day | | |
| Watch Night | | |
| Festival Day | | |
| December 31 Bank Holiday | | |
| National Champagne Day | | |
| Make Up Your Mind Day | | |
| No Interruptions Day | | |
| New Year's Eve | | |
| Hanukkah VI / Rosh Chodesh Tevet | | |
| Restoration Day | | |
| Unlucky Day | | |
| New Year's Day | | |
| Liberation Day | | |
| Republic Day/New Year's Day | | |
| New Year's Day/Independence Day | | |
| Republic Day | | |
| Restoration of the Czech Independence Day | | |
| Independence Day | | |
| Polar Bear Plunge Day | | |
| National Hangover Day | | |
| National Bloody Mary Day | | |
| Diet Resolution Week | | |
| National Silent Record Week | | |
| Celebration Of Life Week | | |
| New Year’s Resolutions Week | | |
| National Mentoring Month | | |
| National CBD Month | | |
| National Bath Safety Month | | |
| National Black Diamond Month | | |
| National Blood Donor Month | | |
| National Braille Literacy Month | | |
| National Hobby Month | | |
| National Hot Tea Month | | |
| National Oatmeal Month | | |
| National Slavery And Human Trafficking Prevention Month | | |
| National Slow Cooking Month | | |
| National Soup Month | | |
| National Sunday Supper Month | | |
| Global Family Day | | |
| Public Domain Day | | |
| National First Foot Day | | |
| Apple Gifting Day | | |
| Z Day | | |
| Ring A Bell Day | | |
| Copyright Law Day | | |
| Euro Day | | |
| Commitment Day | | |
| National Menudo Month | | |
| Universal Hour Of Peace | | |
| Ginuary | | |
| National Clean Up Your Computer Month | | |
| Dry January | | |
| International Brainteaser Month | | |
| Manuary | | |
| Get A Balanced Life Month | | |
| Celebration Of Life Month | | |
| International Creativity Month | | |
| Veganuary Month | | |
| Hanukkah VII | | |
| New Year's Day Holiday | | |
| Heroes’ Day/Ancestors’ Day | | |
| 2nd January (Hogmanay) | | |
| Run It up the Flagpole and See If Anyone Salutes It Day | | |
| Berchtold Day | | |
| Carnival Day | | |
| National Science Fiction Day | | |
| National Personal Trainer Awareness Day | | |
| National Buffet Day | | |
| National Cream Puff Day | | |
| Reconquest Day | | |
| Swiss Cheese Day | | |
| National Pet Travel Safety Day | | |
| 55 Mph Speed Limit Day | | |
| Happy Mew Year For Cats Day | | |
| Motivation And Inspiration Day | | |
| World Introvert Day | | |
| Hanukkah Ends | | |
| New Year's weekend | | |
| Hanukkah VIII | | |
| New Year Holiday Week | | |
| New Year's Day Holiday | | |
| Festival of Sleep Day | | |
| National Chocolate Covered Cherry Day | | |
| National Drinking Straw Day | | |
| National Fruitcake Toss Day | | |
| Revolution Day | | |
| Women Rock! Day | | |
| International Mind-Body Wellness Day | | |
| Humiliation Day | | |
| New Year Holiday Week | | |
| New Year's Day Holiday | | |
| Independence Day | | |
| World Braille Day | | |
| Day of King Amador | | |
| Martyrs of Independence Day | | |
| National Spaghetti Day | | |
| National Trivia Day | | |
| Tom Thumb Day | | |
| Pop Music Chart Day | | |
| Perihelion Day | | |
| Guru Gobind Singh Birthday | | |
| Armenian Christmas Eve | | |
| Twelfth Night | | |
| National Keto Day | | |
| National Bird Day | | |
| National Whipped Cream Day | | |
| National Screenwriters Day | | |
| Epiphany (The Three Wise Men Day) | | |
| Armenian Christmas Day | | |
| Army Day | | |
| Orthodox Christmas Eve | | |
| National Bean Day | | |
| National Shortbread Day | | |
| National Technology Day | | |
| National Cuddle Up Day | | |
| Twelfth Night | | |
| National Take Down The Christmas Tree Day | | |
| World Day For War Orphans | | |
| Apple Tree Day | | |
| National Thank God It’s Monday Day | | |
| Epiphany | | |
| New Year Holiday Week | | |
| National Folic Acid Awareness Week | | |
| Weigh-In Day | | |
| Victory over Genocide Day | | |
| Orthodox Christmas | | |
| Coptic Christmas | | |
| Pioneers Day | | |
| Old Rock Day | | |
| Ethiopian Christmas Day | | |
| National Bobblehead Day | | |
| National Tempura Day | | |
| Constitution Day | | |
| National Pass Gas Day | | |
| Harlem Globetrotters Day | | |
| I’m Not Going To Take It Anymore Day | | |
| Orthodox Christmas Holiday | | |
| Earth's Rotation Day | | |
| National Argyle Day | | |
| National Bubble Bath Day | | |
| National English Toffee Day | | |
| National JoyGerm Day | | |
| National Winter Skin Relief Day | | |
| War On Poverty Day | | |
| Show And Tell At Work Day | | |
| New Year Holiday Week | | |
| National Take The Stairs Day | | |
| Martyrs' Day | | |
| Word Nerd Day | | |
| Peace Agreement Day | | |
| National Apricot Day | | |
| National Law Enforcement Appreciation Day | | |
| National Static Electricity Day | | |
| Day of the Republika Srpska | | |
| International Choreographers Day | | |
| National Cassoulet Day | | |
| Play God Day | | |
| National Balloon Ascension Day | | |
