15 Billie Eilish Halloween Costume Ideas For All You Bad Guys

The music video for "Bad Guy" is possibly Billie's most iconic video to date — it's a musical and visual masterpiece. She has so many outfit changes throughout the song, but the yellow sweatsuit is one of the most notable.

What to wear: An oversize yellow hoodie and matching sweatpants with yellow sneakers; don't forget to pull up the hood.

Billie is the queen of monochromatic ensembles. Case in point: her orange get-up for the 2018 ASCAP Pop Music Awards red carpet. We can't think of a more functional and comfy outfit to wear on Halloween.

What to wear: Knee-length orange gym shorts and an orange t-shirt with a matching windbreaker on top. Bonus points if you also have a pair of orange sneakers handy.

On stage at the 2018 Governors Ball Music Festival, Billie was giving us major lounge vibes in her graphic shirt and sweatpants combo.

What to wear: A light blue, baggy band t-shirt and red track pants with an old pair of chunky sneakers.

If you're the "bad type" or "make your mama sad type," it would be a missed opportunity not to ride around in a toy car on Halloween dressed as Billie. And if you can find a group of friends to do it with you, even better.

What to wear: A red long-sleeved shirt or sweatshirt, shorts, and hightop sneakers. The blue wig is totally optional but highly recommended.

On the red carpet for the 2018 Young Hollywood Party, Billie sported an airbrushed sweatsuit, and it was straight out of a '90s dream. Maybe you have some gear left over from storming Area 51, or maybe you want to try your hand at a little DIY project.

What to wear: An alien-themed long-sleeved shirt and sweatpants with plain white sneakers.

Did Halloween sneak up on you again? Fear not, because Billie's outfit from the "Lovely" music video with Khalid is simple to pull off.

What to wear: All you need are a black top and pants and a ton of chain necklaces to layer on top.

Sticking with the monochromatic theme that Billie loves, her outfit to visit the SiriusXM studio did not disappoint.

What to wear: A white turtleneck under yellow overalls and a bright matching puffer coat on top.

Billie loves a good matching set and chose a lime green option for the 2019 Reading Festival she performed at. With a color scheme straight out of Slytherin House, you will surely look unforgettable this holiday.

What to wear: A tie-dyed oversize t-shirt and shorts and white high-top sneakers (Billie's fave is the Nike Air Force 1 High PSNY). Pull your hair into two loose buns on either side of your head to finish it off.

Cartoons, but make it fashion. On stage at the 2019 Glastonbury Festival, Billie worn one of her most daring outfits to date. The accessories are key here — the more rings and necklaces you can layer on, the better.

What to wear: A wild graphic print, plus every accessory you can find. Throw on a headband, some silver rings and chain necklaces, sunglasses, and, of course, a surgical mask.

Like we said, lime green — otherwise known as slime green — is Billie's color. At 2018's Lollapalooza, she rocked a bright t-shirt with her name on it and a matching beanie.

What to wear: A green t-shirt and matching beanie with a pair of men's swim trunks as shorts.

How could we ever forget about this one? For the 2019 ASCAP Pop Music Awards, one of our favorite cartoon trios made an appearance on Billie's look.

What to wear: Try to dig up a Powerpuff Girls t-shirt and layer it over a white long-sleeved shirt. We're big fans of the crossbody messenger bag for storing extra snacks.

If you're in a pinch, take some inspiration from Billie's performance at the 2018 Outside Lands Music Arts.

What to wear: A sports t-shirt, white shorts, and a pair of sneakers get the point across. A silver wig would also be ideal.

You can get your friends involved with this look. While promoting her album, When We All Fall Asleep, Where Do We Go?, Billie wore sweats with her name written all over them. It may be mistaken for an Orange Is the New Black costume, but that's not the worst thing in the world.

What to wear: An orange hoodie and sweatpants that you've written on in black marker.

If you're feeling moody and not so much in the Halloween spirit, Billie's outfit in her music video for "When the Party's Over" is easy to pull off. Honestly, you probably already have it in your closet.

What to wear: A white t-shirt, leggings, and sneakers. You'll also need a blue wig, chunky silver jewelry, and some costume makeup (if you've seen the video, you know).

Here, Billie channeled a heavy metal/Travis Scott ethos with a flame-covered t-shirt and shorts combo. That, and her green hair pulled into two pigtail buns, has Halloween written all over it.

What to wear: A t-shirt sporting flames on it, a silver choker, and black sneakers.