Why do we wear costumes on Halloween? The answer is much more complicated than just “scary”.
Every October, hundreds of millions of people around the world start doing the same thing: spending a few dozen dollars to dress up as someone they would never otherwise be.
In 2026, total U.S. spending on Halloween costumes is projected to reach $4.4 billion, with 71% of celebrants buying a costume for themselves, their kids, or their pets. That number is higher than the GDP of many countries.
But there is one fundamental question most people have never seriously considered: why do we dress up as someone else on Halloween?
The answer dates back to a night more than two thousand years ago. On that night, the Celts didn’t wear animal skins for fun. They did it to survive.
2,000 years ago, Halloween costumes were a “disguise survival battle”
The story begins with the ancient Celts’ festival of Samhain. It was the Celtic New Year, marking the end of summer and the beginning of winter. The Celts believed that on the night of October 31, the door between the world of the living and the world of the dead would open, allowing ghosts, demons, and all kinds of supernatural beings to roam the earth.
Faced with these invisible threats, the Celts came up with a plan that seems absurd today but was utterly serious at the time: dressing up as them.
Research from the American Folklife Center at the Library of Congress points out that the Celts often wore animal skins — sometimes with the animal’s head attached — to confuse evil spirits and even avoid being possessed. If the spirits couldn’t tell you were alive, they wouldn’t come after you. They also blackened their faces with charcoal, wore their clothes inside out, and made strange noises so that the god of death wouldn’t recognize them.
In other words, this wasn’t a “costume party” — it was “survival disguise.” You dressed up as a ghost not because you liked ghosts, but because you didn’t want to be taken by one.
The Middle Ages: costumes went from “tricking ghosts” to “trading for food”
By the Middle Ages, the function of Halloween costumes underwent its first transformation.
In 835 AD, Christianity designated November 1 as All Saints’ Day, attempting to overlay the Celtic festival of Samhain with a day honoring saints. But the custom of wearing costumes didn’t disappear — the reason just changed.
Poor people in England and Ireland began an activity called “souling”: on All Saints’ Day and All Souls’ Day, they went door-to-door, sang a soul song, and asked for small cakes called “soul cakes.” In exchange, they prayed for the dead relatives of the donors. Shakespeare even wrote about this custom in The Two Gentlemen of Verona.
Meanwhile, young people in Scotland and Ireland developed “guising”: after dressing up, they would go door-to-door singing, telling jokes, performing small acts, and receiving a little food or loose change in return. The earliest written record is from Scotland in 1585.
The function of costumes shifted from protecting yourself to trading for food. You dress up as someone else not because you fear ghosts, but because you want neighbors to open their doors.
In the 19th century, Irish immigrants brought the costume tradition to America
Halloween costumes truly became what they are today thanks to Irish immigrants.
After the Irish potato famine of the 1840s, about 4.5 million Irish people immigrated to America, carrying the entire Samhain tradition with them—bonfires, costumes, and going door to door for food.
But in America, things changed. In the late 19th century, Halloween gradually shifted from an Irish immigrant holiday to a family holiday. In 1894, a Halloween parade was recorded in Scranton, Pennsylvania; in 1895, Topeka, Kansas also held one. The costumes in the parades were homemade, depicting ghosts, witches, and assorted ghouls.
The real turning point came in the 1930s. Two factors worked together: during the Great Depression, American society wanted to steer young people away from Halloween pranks and toward positive activities, and commercial companies smelled opportunity. In the 1930s, A.S. Fishbach obtained a license from Disney and began producing Mickey Mouse and Donald Duck Halloween costumes. Costumes went from homemade to store-bought, from monsters to characters.
From this moment on, the core logic of Halloween costumes completely flipped. Before, you wore a costume to avoid being recognized. Now you wear a costume to be recognized—as Spider-Man, Wednesday Addams, or the most popular movie character of the year.
2026: The new function of Halloween costumes
So why do people still dress up today?
The 2026 data offers a more practical answer than tradition: because the costume is the cheapest identity experiment of the holiday.
An NRF survey shows that total Halloween spending in 2026 is projected at $13.5 billion, or $115.14 per person, roughly flat with 2025. What's more notable is how consumers spend: 34% of people explicitly said they would look for products that can be reused or repurposed at Halloween. This means more and more people are treating Halloween costumes as an investment rather than a one-time expense.
And the crowd getting into costume is growing, 71% of celebrants buy costumes — not just for kids (kids' costumes about $1.5 billion), adult costume spending is expected to reach $2 billion, and pet costumes nearly $1 billion (about $920 million), pet costume growth is especially strong, up 22.9% year over year, this tells us one thing: Halloween costumes are no longer just about people, but a family affair — including furry kids — a game of identity everyone plays together
From being afraid of ghosts to being one: the ultimate twist on dressing up
Looking back at two thousand years of history, Halloween costumes have undergone a perfect reversal:
500 BC: wearing animal hides to keep ghosts from recognizing you
Middle Ages: dressing up and going door to door to trade for a soul cake
1930s: buying a Disney costume so people would recognize you as Mickey Mouse
2026: spending $115 on a costume is about being someone you're not for one day on Halloween night
Sociologists and folklorists still have no fully consistent answer to why we dress up, but one explanation feels closest to the truth: Halloween is the only night of the year when you can be anyone and no one will question you
On this night, an accountant who usually wears a suit can become a pirate. A high schooler in a daily uniform can become a zombie. An introvert can put on a mask and do something they'd never dare to do normally
The essence of dressing up is not becoming a ghost but becoming the person you want to be; two thousand years ago, that person was a living human not taken by ghosts; and now, that person can be anything
From fearing ghosts to being a ghost, and then to being the person you want to be — the 2,000 years of Halloween costumes are actually 2,000 years of humanity using imagination to fight fear and then using imagination to create joy
